| 1. |
- Boström, Mathias, et al.
(författare)
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Casimir attractive-repulsive transition in MEMS
- 2012
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Ingår i: European Physical Journal B. - : Springer Science and Business Media LLC. - 1434-6028 .- 1434-6036. ; 85:11, s. 377-
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Tidskriftsartikel (refereegranskat)abstract
- Unwanted stiction in micro-and nanomechanical (NEMS/MEMS) systems due to dispersion (van der Waals, or Casimir) forces is a significant hurdle in the fabrication of systems with moving parts on these length scales. Introducing a suitably dielectric liquid in the interspace between bodies has previously been demonstrated to render dispersion forces repulsive, or even to switch sign as a function of separation. Making use of recently available permittivity data calculated by us we show that such a remarkable nonmonotonic Casimir force, changing from attractive to repulsive as separation increases, can in fact be observed in systems where constituent materials are in standard NEMS/MEMS use requiring no special or exotic materials. No such nonmonotonic behaviour has been measured to date. We calculate the force between a silica sphere and a flat surface of either zinc oxide or hafnia, two materials which are among the most prominent for practical microelectrical and microoptical devices. Our results explicate the need for highly accurate permittivity functions of the materials involved for frequencies from optical to far-infrared frequencies. A careful analysis of the Casimir interaction is presented, and we show how the change in the sign of the interaction can be understood as a result of multiple crossings of the dielectric functions of the three media involved in a given set-up.
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| 2. |
- Boström, Mathias, et al.
(författare)
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Casimir force between atomically thin gold films
- 2013
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Ingår i: European Physical Journal B. - : Springer Science and Business Media LLC. - 1434-6028 .- 1434-6036. ; 86:2, s. 43-
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Tidskriftsartikel (refereegranskat)abstract
- We have used density functional theory to calculate the anisotropic dielectric functions for ultrathin gold sheets (composed of 1, 3, 6, and 15 atomic layers). Such films are important components in nano-electromechanical systems. When using correct dielectric functions rather than bulk gold dielectric functions we predict an enhanced attractive Casimir-Lifshitz force (at most around 20%) between two atomically thin gold sheets. For thicker sheets the dielectric properties and the corresponding Casimir forces approach those of gold half-spaces. The magnitude of the corrections that we predict should, within the today's level of accuracy in Casimir force measurements, be clearly detectable.
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| 3. |
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| 4. |
- Kennergren, Charles, 1948, et al.
(författare)
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A single-centre experience of over one thousand lead extractions.
- 2009
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Ingår i: Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology. - : Oxford University Press (OUP). - 1532-2092. ; 11:5, s. 612-7
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: The aim of the study was to present a single-centre experience of pacemaker and implantable cardioverter defibrillator (ICD) lead extraction using different methods, mainly laser-assisted extraction. METHODS AND RESULTS: Data from 1032 leads and 647 procedures were gathered. A step-by-step approach using different techniques while performing an ongoing risk-benefit analysis was used. The most common indications were local infection, systemic infection, non-functional lead, elective lead replacement, and J-wire fracture. Mean implantation time for all leads was 69 months and for laser-extracted leads 91 months. Laser technique was used to extract 60% of the leads, 29% were manually extracted, 6% extracted with mechanical tools, 4% were surgically removed, and 0.6% extracted by a femoral approach. Failure rate was 0.7%, and major complication rate was 0.9%. No extraction-related mortality occurred. Median time for laser extraction was 2 min. Long implantation time was not a risk factor for failure or for complication. CONCLUSION: Pacing and ICD leads can safely, successfully, and effectively be extracted. Leads can often be extracted by a superior transvenous approach; however, open-chest and femoral extractions are still required. Laser-assisted lead extraction proved to be a useful technique to extract leads that could not be removed by manual traction. The results indicate that the paradigm of abandoning redundant leads, instead of removing them, may have to be reconsidered.
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| 5. |
- Kennergren, Charles, 1948
(författare)
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Cardiac implantable electronic device treatment: taking care of complications.
- 2009
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Ingår i: Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology. - : Oxford University Press (OUP). - 1532-2092. ; 11:11, s. 1419-20
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Tidskriftsartikel (refereegranskat)
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| 6. |
- Kennergren, Charles, 1948, et al.
(författare)
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Laser-assisted lead extraction: the European experience.
- 2007
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Ingår i: Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology. - : Oxford University Press (OUP). - 1099-5129. ; 9:8, s. 651-6
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: The aim of this study is to investigate the safety and effectiveness of Excimer laser-assisted lead extraction in Europe. The final European multi-centre study experience is presented. METHOD AND RESULTS: The Excimer is a cool cutting laser (50 degrees C) with a wavelength of 308 nm. The energy is emitted from the tip of a flexible sheath and is absorbed by proteins and lipids, 64% of the energy is absorbed at a tissue depth of 0.06 mm. The sheath is positioned over the lead, and the fibrosis surrounding the lead is vaporized while advancing the sheath without damaging other leads. From August 1996 to March 2001, 383 leads (170 atrial, 213 ventricular) in 292 patients (mean age 61.6 years, range 13-96) were extracted at 14 European centres. Mean implantation time was 74 months (3-358). Most frequent indications were pocket infection (26%), non-functional leads (21%), patient morbidity (21%), septicaemia or endocarditis (14%), erosion (5%), and lead interference (8%). Median extraction time was 15 min (1-300). Complete extraction was achieved in 90.9% of the leads and partial extraction in 3.4%. Extraction failed in 5.7% of the leads. Major complications = perforations caused 10/22 (3.4/5.7%) of the failures. Most partially extracted patients were considered clinically successful, as only minor lead parts without clinical significance were left. Femoral non-laser technique was used to remove 8/12 of the non-complication failures. The total complication rate, including five minor complications (1.7%), was 5.1%. No in-hospital mortality occurred. CONCLUSION: Pacing and implantable cardioverter-defibrillator leads can safely, effectively, and predictably be extracted. Open-heart extractions can be limited to special cases. The results indicate that the traditional policy of abandoning redundant leads, instead of removing them, may be obsolete in many patients.
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| 7. |
- Olofsson, Sigvard, 1948, et al.
(författare)
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Viral O-GalNAc peptide epitopes: a novel potential target in viral envelope glycoproteins.
- 2016
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Ingår i: Reviews in medical virology. - : Wiley. - 1099-1654 .- 1052-9276. ; 26:1, s. 34-48
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Tidskriftsartikel (refereegranskat)abstract
- Viral envelope glycoproteins are major targets for antibodies that bind to and inactivate viral particles. The capacity of a viral vaccine to induce virus-neutralizing antibodies is often used as a marker for vaccine efficacy. Yet the number of known neutralization target epitopes is restricted owing to various viral escape mechanisms. We expand the range of possible viral glycoprotein targets, by presenting a previously unknown type of viral glycoprotein epitope based on a short peptide stretch modified with small O-linked glycans. Besides being immunologically active, these epitopes have a high potential for antigenic variation. Thus, sera from patients infected with EBV develop individual IgG responses addressing the different possible glycopeptide glycoforms of one short peptide backbone that reflect individual variations in the course of virus infection. In contrast, in HSV type 2 meningitis patients, CSF antibodies are focussed to only one single glycoform peptide of a major viral glycoprotein. Thus, dependent on the viral disease, the serological response may be variable or constant with respect to the number of targeted peptide glycoforms. Mapping of these epitopes relies on a novel three-step procedure that identifies any reactive viral O-glycosyl peptide epitope with respect to (i) relevant peptide sequence, (ii) the reactive glycoform out of several possible glycopeptide isomers of that peptide sequence, and (iii) possibly tolerated carbohydrate or peptide structural variations at glycosylation sites. In conclusion, the viral O-glycosyl peptide epitopes may be of relevance for development of subunit vaccines and for improved serodiagnosis of viral diseases.
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| 8. |
- Raak, Ragnhild, 1948-, et al.
(författare)
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Coping strategies and life satisfaction in subgrouped fibromyalgia patients
- 2003
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Ingår i: Biological Research for Nursing. - : SAGE Publications. - 1099-8004 .- 1552-4175. ; 4:3, s. 193-202
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Tidskriftsartikel (refereegranskat)abstract
- The present study describes pain- and stress-coping strategies and life satisfaction in subgroups of fibromyalgia patients. Thirty-two females with fibromyalgia syndrome (FMS) and 21 healthy pain-free women were studied. Those with FMS were classified as thermal (both heat and cold) pain sensitive or slightly cold pain sensitive based on pain thresholds determined using a Thermotest device. Global stress-coping styles, life satisfaction, and specific pain-coping strategies were measured. Patients classified as thermal pain sensitive were affected by physical symptoms to a greater extent than were those classified as slightly cold pain sensitive. The thermal pain sensitive group used more diverting attention coping strategies than the slightly cold pain sensitive group did. Separating fibromyalgia patients into subgroups might increase the potential for improving nursing care of these patients. Through the use of effective coping strategies in dealing with stress and pain, life satisfaction may also be enhanced.
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| 9. |
- Raak, Ragnhild, 1948-, et al.
(författare)
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Thermal thresholds and catastrophizing in individuals with chronic pain after whiplash injury
- 2006
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Ingår i: Biological Research for Nursing. - : SAGE Publications. - 1099-8004 .- 1552-4175. ; 8:2, s. 138-146
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Tidskriftsartikel (refereegranskat)abstract
- Thermal sensitivity, thermal pain thresholds, and catastrophizing were examined in individuals with whiplash associated disorders (WAD) and in healthy pain-free participants. Quantitative sensory testing (QST) was used to measure skin sensitivity to cold and warmth and cold and heat pain thresholds over both the thenar eminence and the trapezius muscle (TrM) in 17 participants with WAD (age 50.8± 11.3 years) and 18 healthy participants (age 44.8± 10.2 years). The Pain Catastrophizing Scale (PCS) was used to determine pain coping strategies, and visual analogue scales were used for self-assessment of current background pain in individuals in the WAD group as well as experienced pain intensity and unpleasantness after QST and sleep quality in all participants. There were significant differences in warmth threshold and cold and heat pain thresholds of the TrM site between the WAD and pain-free groups. Significant differences between the two groups were also found for the catastrophizing dimension of helplessness in the PCS and in self-assessed quality of sleep. A correlational analysis showed that current background pain is significantly correlated with both cold discrimination and cold pain threshold in the skin over the TrM in individuals with WAD. These findings imply that thermal sensitivity is an important factor to consider in providing nursing care to individuals with WAD. Because biopsychosocial factors also influence the experience of pain in individuals with WAD, the role of nurses includes not only the description of the pain phenomenon but also the identification of relieving and aggravating factors.
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| 10. |
- Salander, Pär, 1948-
(författare)
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Attributions of lung cancer : my own illness is hardly caused by smoking
- 2007
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Ingår i: Psycho-Oncology. - : Wiley. - 1057-9249 .- 1099-1611. ; 16:6, s. 587-592
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Tidskriftsartikel (refereegranskat)abstract
- People experiencing unexpected negative events tend to make sense of the situation through causal attributions. It seems that having some sort of answer to “why-me” makes the event less shattering and the world more controllable. We know for instance that the great majority of women with breast cancer tend to have clear ideas about its causes. Lung cancer, in contrast to breast cancer, has a well-known significant cause, as smoking explains about 80% of the incidence. This paper deals with the attribution process in lung cancer. It examines how lung cancer patients attribute the cause to their disease and how this relates to an understanding of how people deal with strain. Twenty-three patients with advanced non-small-cell lung cancer were consecutively followed by means of repeated interviews throughout the course of the disease. It emerged that among the smokers the most common attribution was “don’t know” – smoking was not seen as the prime cause to their cancer. This finding is discussed in relation to the few earlier somewhat contradictory studies that exist and it is argued that the finding is according well with the concept of ‘disavowal’ being the central process concerned in dealing with strain.
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