Showing papers by "Linköping University published in 2007"

EULAR evidence based recommendations for the management of fibromyalgia syndrome

Abstract: Objective: To develop evidence-based recommendations for the management of fibromyalgia syndrome. Methods: A multidisciplinary task force was formed representing 11 European countries. The design o ...

Spatial, Temporal, and Species Variation in Prevalence of Influenza A Viruses in Wild Migratory Birds

Abstract: Although extensive data exist on avian influenza in wild birds in North America, limited information is available from elsewhere, including Europe. Here, molecular diagnostic tools were employed for high-throughput surveillance of migratory birds, as an alternative to classical labor-intensive methods of virus isolation in eggs. This study included 36,809 samples from 323 bird species belonging to 18 orders, of which only 25 species of three orders were positive for influenza A virus. Information on species, locations, and timing is provided for all samples tested. Seven previously unknown host species for avian influenza virus were identified: barnacle goose, bean goose, brent goose, pink-footed goose, bewick's swan, common gull, and guillemot. Dabbling ducks were more frequently infected than other ducks and Anseriformes; this distinction was probably related to bird behavior rather than population sizes. Waders did not appear to play a role in the epidemiology of avian influenza in Europe, in contrast to the Americas. The high virus prevalence in ducks in Europe in spring as compared with North America could explain the differences in virus–host ecology between these continents. Most influenza A virus subtypes were detected in ducks, but H13 and H16 subtypes were detected primarily in gulls. Viruses of subtype H6 were more promiscuous in host range than other subtypes. Temporal and spatial variation in influenza virus prevalence in wild birds was observed, with influenza A virus prevalence varying by sampling location; this is probably related to migration patterns from northeast to southwest and a higher prevalence farther north along the flyways. We discuss the ecology and epidemiology of avian influenza A virus in wild birds in relation to host ecology and compare our results with published studies. These data are useful for designing new surveillance programs and are particularly relevant due to increased interest in avian influenza in wild birds.

Organic materials for printed electronics.

Abstract: Organic materials can offer a low-cost alternative for printed electronics and flexible displays. However, research in these systems must exploit the differences - via molecular-level control of functionality - compared with inorganic electronics if they are to become commercially viable.

New materials for micro-scale sensors and actuators An engineering review

Abstract: This paper provides a detailed overview of developments in transducer materials technology relating to their current and future applications in micro-scale devices. Recent advances in piezoelectric, magnetostrictive and shape-memory alloy systems are discussed and emerging transducer materials such as magnetic nanoparticles, expandable micro-spheres and conductive polymers are introduced. Materials properties, transducer mechanisms and end applications are described and the potential for integration of the materials with ancillary systems components is viewed as an essential consideration. The review concludes with a short discussion of structural polymers that are extending the range of micro-fabrication techniques available to designers and production engineers beyond the limitations of silicon fabrication technology.

Probiotics in prevention of IgE-associated eczema: A double-blind, randomized, placebo-controlled trial

Abstract: Background An altered microbial exposure may underlie the increase of allergic diseases in affluent societies. Probiotics may alleviate and even prevent eczema in infants. Objective To prevent eczema and sensitization in infants with a family history of allergic disease by oral supplementation with the probiotic Lactobacillus reuteri . Methods Double-blind, randomized, placebo-controlled trial, which comprised 232 families with allergic disease, of whom 188 completed the study. The mothers received L reuteri ATCC 55730 (1 × 10 8 colony forming units) daily from gestational week 36 until delivery. Their babies then continued with the same product from birth until 12 months of age and were followed up for another year. Primary outcome was allergic disease, with or without positive skin prick test or circulating IgE to food allergens. Results The cumulative incidence of eczema was similar, 36% in the treated versus 34% in the placebo group. The L reuteri group had less IgE-associated eczema during the second year, 8% versus 20% ( P = .02), however. Skin prick test reactivity was also less common in the treated than in the placebo group, significantly so for infants with mothers with allergies, 14% versus 31% ( P = .02). Wheeze and other potentially allergic diseases were not affected. Conclusion Although a preventive effect of probiotics on infant eczema was not confirmed, the treated infants had less IgE-associated eczema at 2 years of age and therefore possibly run a reduced risk to develop later respiratory allergic disease. Clinical implication Probiotics may reduce the incidence of IgE-associated eczema in infancy.

Towards woven logic from organic electronic fibres.

Abstract: The use of organic polymers for electronic functions is mainly motivated by the low-end applications, where low cost rather than advanced performance is a driving force. Materials and processing me ...

Guidelines on the diagnosis and management of iron deficiency and anemia in inflammatory bowel diseases

Abstract: Anemia is a common complication of inflammatory bowel diseases. An international working party has formed and developed guidelines for evaluation and treatment of anemia and iron deficiency that should serve practicing gastroenterologists. Within a total of 16 statements, recommendations are made regarding diagnostic measures to screen for iron- and other anemia-related deficiencies regarding the triggers for medical intervention, treatment goals, and appropriate therapies. Anemia is a common cause of hospitalization, prevents physicians from discharging hospitalized patients, and is one of the most frequent comorbid conditions in patients with inflammatory bowel disease. It therefore needs appropriate attention and specific care.

The Swedish rectal cancer registry

Abstract: Background: An audit of all patients with rectal cancer in Sweden was launched in 1995. This is the first report from the Swedish Rectal Cancer Registry (SRCR). Methods: Between 1995 and 2003, 13 434 patients treated for adenocarcinoma of the rectum were registered with the SRCR, there were approximately 1500 new patients annually. Results: Approximately half had an anterior resection, a quarter an abdominoperineal resection and 15 per cent a Hartmann's procedure. The median 30-day postoperative mortality rate was 2.4 per cent and the overall postoperative morbidity rate was 35.0 per cent. The 5-year cancer-specific survival rate was 62.3 percent. The 5-year relative survival rate was 70.1 percent after anterior resection, 59.8 per cent after abdominoperineal resection and 39.8 per cent after a Hartmann's procedure. The crude 5-year local recurrence rate was 9.5 per cent overall, 6.1 per cent after preoperative radiotherapy and 11.4 per cent after surgery alone. For 3868 patients who had a locally curative procedure the local recurrence rate was 7-4 per cent overall, 5.9 per cent for those who had radiotherapy and 10.2 per cent for those who did not. The local recurrence rate was 2.9 per cent (28 of 968) for stage I disease, 7.9 per cent (112 of 1418) for stage II, 13.9 per cent (188 of 1357) for stage III and 8.5 per cent (45 of 532) for stage IV. Conclusion: These good population-based results are due, in part, to the nationwide prospective quality assurance registration. Copyright © 2007 British Journal of Surgery Society Ltd Published by John Wiley & Sons Ltd.

Printable All-Organic Electrochromic Active-Matrix Displays

Abstract: All-organic active matrix addressed displays based on electrochemical smart pixels made on flexible substrates are reported. Each individual smart pixel device combines an electrochemical transisto ...

Nonsurgical treatment of appendiceal abscess or phlegmon: a systematic review and meta-analysis.

Abstract: Objective:A systematic review of the nonsurgical treatment of patients with appendiceal abscess or phlegmon, with emphasis on the success rate, need for drainage of abscesses, risk of undetected serious disease, and need for interval appendectomy to prevent recurrence.Summary Background Data:Patient

Electronic Control of Ca2+ Signalling in Neuronal Cells using an Organic Electronic Ion Pump

Abstract: Cells and tissues use finely regulated ion fluxes for their intra- and intercellular communication. Technologies providing spatial and temporal control for studies of such fluxes are however, limited. We have developed an electrophoretic ion pump made of poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulphonate) (PEDOT:PSS) to mediate electronic control of the ion homeostasis in neurons. Ion delivery from a source reservoir to a receiving electrolyte via a PEDOT:PSS thin-film channel was achieved by electronic addressing. Ions are delivered in high quantities at an associated on/off ratio exceeding 300. This induces physiological signalling events that can be recorded at the single-cell level. Furthermore, miniaturization of the device to a 50-microm-wide channel allows for stimulation of individual cells. As this technology platform allows for electronic control of ion signalling in individual cells with proper spatial and temporal resolution, it will be useful in further studies of communication in biological systems.

Tuning LDA+U for electron localization and structure at oxygen vacancies in ceria

Abstract: We examine the real space structure and the electronic structure (particularly Ce4f electron localization) of oxygen vacancies in CeO2 (ceria) as a function of U in density functional theory studies with the rotationally invariant forms of the LDA+U and GGA+U functionals. The four nearest neighbor Ce ions always relax outwards, with those not carrying localized Ce4f charge moving furthest. Several quantification schemes show that the charge starts to become localized at U≈3eV and that the degree of localization reaches a maximum at ∼6eV for LDA+U or at ∼5.5eV for GGA+U. For higher U it decreases rapidly as charge is transferred onto second neighbor O ions and beyond. The localization is never into atomic corelike states; at maximum localization about 80–90% of the Ce4f charge is located on the two nearest neighboring Ce ions. However, if we look at the total atomic charge we find that the two ions only make a net gain of (0.2–0.4)e each, so localization is actually very incomplete, with localization of Ce4f electrons coming at the expense of moving other electrons off the Ce ions. We have also revisited some properties of defect-free ceria and find that with LDA+U the crystal structure is actually best described with U=3–4eV, while the experimental band structure is obtained with U=7–8eV. (For GGA+U the lattice parameters worsen for U>0eV, but the band structure is similar to LDA+U.) The best overall choice is U≈6eV with LDA+U and ≈5.5eV for GGA+U, since the localization is most important, but a consistent choice for both CeO2 and Ce2O3, with and without vacancies, is hard to find.

A UAV search and rescue scenario with human body detection and geolocalization

Abstract: The use of Unmanned Aerial Vehicles (UAVs) which can operate autonomously in dynamic and complex operational environments is becoming increasingly more common. The UAVTech Lab, is pursuing a long term research endeavour related to the development of future aviation systems which try and push the envelope in terms of using and integrating high-level deliberative or AI functionality with traditional reactive and control components in autonomous UAV systems. In order to carry on such research, one requires challenging mission scenarios which force such integration and development. In this paper, one of these challenging emergency services mission scenarios is presented. It involves search and rescue for injured civilians by UAVs. In leg I of the mission, UAVs scan designated areas and try to identify injured civilians. In leg II of the mission, an attempt is made to deliver medical and other supplies to identified victims. We show how far we have come in implementing and executing such a challenging mission in realistic urban scenarios.

Modeling of CeO2, Ce2O3, and CeO2−x in the LDA+U formalism

Abstract: The electronic structure and thermodynamic properties of CeO2 and Ce2O3 have been studied from first principles by the all-electron projector-augmented-wave (PAW) method, as implemented in the ab i ...

PIK3CA Mutations and PTEN Loss Correlate with Similar Prognostic Factors and Are Not Mutually Exclusive in Breast Cancer

Abstract: Purpose: The phosphatidylinositol 3'-kinase/Akt pathway is frequently altered in breast cancer. PTEN, a phosphatase that opposes the effect of phosphatidylinositol 3'-kinase, can be mutated or lost ...

A New Donor–Acceptor–Donor Polyfluorene Copolymer with Balanced Electron and Hole Mobility†

Abstract: A New Donor-Acceptor-Donor Polyfluorence Copolymer with Balanced Electron and Hole Mobility

Genetic variants of CYP3A5, CYP2D6, SULT1A1, UGT2B15 and tamoxifen response in postmenopausal patients with breast cancer

Abstract: Introduction Tamoxifen therapy reduces the risk of recurrence and prolongs the survival of oestrogen-receptor-positive patients with breast cancer Even if most patients benefit from tamoxifen, many breast tumours either fail to respond or become resistant Because tamoxifen is extensively metabolised by polymorphic enzymes, one proposed mechanism underlying the resistance is altered metabolism In the present study we investigated the prognostic and/or predictive value of functional polymorphisms in cytochrome P450 3A5 CYP3A5 (*3), CYP2D6 (*4), sulphotransferase 1A1 (SULT1A1; *2) and UDP-glucuronosyltransferase 2B15 (UGT2B15; *2) in tamoxifen-treated patients with breast cancer

Treatment of social phobia: randomised trial of internet-delivered cognitive-behavioural therapy with telephone support.

Abstract: Background Although effective therapies for social phobia exist, many individuals refrain from seeking treatment owing to the embarrassment associated with help-seeking. Internet-based cognitive–behavioural self-help can be an alternative, but adherence is a problem. Aims To evaluate a 9-week programme of internet-based therapy designed to increase treatment adherence by the addition of short weekly telephone calls, nine in all, with a total duration of 95 min. Method In a randomised controlled trial the effects of internet-based cognitive–behavioural therapy in the treatment group ( n =29) were compared with a waiting-list control group ( n =28). Results Compared with the control group the treated participants experienced greater reductions on measures of general and social anxiety, avoidance and depression. Adherence to treatment was high, with 93% finishing the complete treatment package. One year later all improvements were maintained. Conclusions This study provides evidence to support the use of internet-based treatment supplemented by short, weekly telephone calls.

Autophagy, organelles and ageing.

Abstract: As a result of insufficient digestion of oxidatively damaged macromolecules and organelles by autophagy and other degradative systems, long-lived postmitotic cells, such as cardiac myocytes, neurons and retinal pigment epithelial cells, progressively accumulate biological 'garbage' ('waste' materials). The latter include lipofuscin (a non-degradable intralysosomal polymeric substance), defective mitochondria and other organelles, and aberrant proteins, often forming aggregates (aggresomes). An interaction between senescent lipofuscin-loaded lysosomes and mitochondria seems to play a pivotal role in the progress of cellular ageing. Lipofuscin deposition hampers autophagic mitochondrial turnover, promoting the accumulation of senescent mitochondria, which are deficient in ATP production but produce increased amounts of reactive oxygen species. Increased oxidative stress, in turn, further enhances damage to both mitochondria and lysosomes, thus diminishing adaptability, triggering mitochondrial and lysosomal pro-apoptotic pathways, and culminating in cell death.

Electrode Grids for ITO Free Organic Photovoltaic Devices

Abstract: Organic materials, such as conjugated polymers, have emerged as a promising alternative for the production of inexpensive and flexible photovoltaic cells. As conjugated polymers are soluble, liquid based printing techniques enable production on large scale to a price much lower than that for inorganic based solar cells. Present day state of the art conjugated polymer photovoltaic cells are comprised by blends of a semiconducting polymer and a soluble derivative of fullerene molecules. Such bulk heterojunction solar cells now show power conversion efficiencies of up to 4-6%. The quantum efficiency of thin film organic solar cells is however still limited by several processes, of which the most prominent limitations are the comparatively low mobility and the high level of charge recombination. Hence organic cells do not yet perform as well as their more expensive inorganic counterparts. In order to overcome this present drawback of conjugated polymer photovoltaics, efforts are continuously devoted to developing materials or devices with increased absorption or with better charge carrier transporting properties. The latter can be facilitated by increasing the mobility of the pure material or by introducing beneficial morphology to prevent carrier recombination. Minimizing the active layer film thickness is an alternative route to collect more of the generated free charge carriers. However, a minimum film thickness is always required for sufficient photon absorption. A further limitation for low cost large scale production has been the dependence on expensive transparent electrodes such as indium tin oxide. The development of cheaper electrodes compatible with fast processing is therefore of high importance. The primary aim of this work has been to increase the absorption in solar cells made from thin films of organic materials. Device construction, deploying new geometries, and evaluation of different methods to provide for light trapping and photon recycling have been strived for. Different routes to construct and incorporate light trapping structures that enable higher photon absorption in a thinner film are presented. By recycling the reflected photons and enhancing the optical path length within a thinner cell, the absorption rate, as well as the collection of more charge carriers, is provided for. Attempts have been performed by utilizing a range of different structures with feature sizes ranging from nanometers up to centimeters. Surface plasmons, Lambertian scatterers, micro lenses, tandem cells as well as larger folded cell structures have been evaluated. Naturally, some of these methods have turned out to be more successful than others. From this work it can nevertheless be concluded that proper light trapping, in thin films of organic materials for photovoltaic energy conversion, is a technique capable of improving the cell performance. In addition to the study of light trapping, two new alternative electrodes for polymer photovoltaic devices are suggested and evaluated.

Ethical and Methodological Issues in Interviewing Persons With Dementia

Abstract: People with dementia have previously not been active participants in research, with ethical difficulties often being cited as the reason for this. A wider inclusion of people with dementia in research raises several ethical and methodological challenges. This article adds to the emerging debate by reflecting on the ethical and methodological issues raised during an interview study involving people with dementia and their spouses. The study sought to explore the impact of living with dementia. We argue that there is support for the inclusion of people with dementia in research and that the benefits of participation usually far outweigh the risks, particularly when a ;safe context' has been created. The role of gatekeepers as potentially responsible for excluding people with dementia needs further consideration, with particular reference to the appropriateness of viewing consent as a primarily cognitive, universalistic and exclusionary event as opposed to a more particularistic, inclusive and context relevant process.

Learning in focus groups: an analytical dimension for enhancing focus group research

Abstract: The focus group is a research methodology in which a small group of participants gathers to discuss a specified issue under the guidance of a moderator. The discussions are tape-recorded, transcrib ...

Internet-delivered treatments with or without therapist input: does the therapist factor have implications for efficacy and cost?

Abstract: Psychiatric problems such as mood and anxiety disorders are highly prevalent and are associated with high societal costs and individual suffering. Evidence-based psychological treatments obtain good results but are not available to the required extent due to the lack of practitioners with adequate training. One way to solve this problem is to provide minimal-contact self-help treatments, for example, with the assistance of computers. Recently, internet-delivered cognitive-behavioral treatment has been tested in a series of controlled trials. However, the interventions come in many forms with different levels and kinds of therapist input, which have implications for the costs of the treatments and possibly their effectiveness. In this review we found evidence for a strong correlation between therapist input and outcome. While emerging evidence attests to the efficacy of internet-delivered treatment when at least minimal therapist guidance is provided, most studies in the field have not included a formal evaluation of cost-effectiveness. Future research needs are discussed.

Meta-Analysis of Public Transport Demand

Abstract: The present study uses meta-regression in order to explain the wide variation in elasticity estimates obtained in previous demand studies, and provide summaries of several bus demand elasticities.O ...

Formation and Dynamics of Shock Waves in the Degasperis-Procesi Equation

Abstract: Solutions of the Degasperis-Procesi nonlinear wave equation may develop discontinuities in finite time As shown by Coclite and Karlsen, there is a uniquely determined entropy weak solution which provides a natural continuation of the solution past such a point Here we study this phenomenon in detail for solutions involving interacting peakons and antipeakons We show that a jump discontinuity forms when a peakon collides with an antipeakon, and that the entropy weak solution in this case is described by a "shockpeakon" ansatz reducing the PDE to a system of ODEs for positions, momenta, and shock strengths