1. |
- Berggren, Magnus, et al.
(författare)
-
Ion Electron-Coupled Functionality in Materials and Devices Based on Conjugated Polymers
- 2019
-
Ingår i: Advanced Materials. - : Wiley-VCH Verlagsgesellschaft. - 0935-9648 .- 1521-4095. ; 31:22
-
Forskningsöversikt (refereegranskat)abstract
- The coupling between charge accumulation in a conjugated polymer and the ionic charge compensation, provided from an electrolyte, defines the mode of operation in a vast array of different organic electrochemical devices. The most explored mixed organic ion-electron conductor, serving as the active electrode in these devices, is poly(3,4-ethyelenedioxythiophene) doped with polystyrelensulfonate (PEDOT:PSS). In this progress report, scientists of the Laboratory of Organic Electronics at Linkoping University review some of the achievements derived over the last two decades in the field of organic electrochemical devices, in particular including PEDOT:PSS as the active material. The recently established understanding of the volumetric capacitance and the mixed ion-electron charge transport properties of PEDOT are described along with examples of various devices and phenomena utilizing this ion-electron coupling, such as the organic electrochemical transistor, ionic-electronic thermodiffusion, electrochromic devices, surface switches, and more. One of the pioneers in this exciting research field is Prof. Olle Inganas and the authors of this progress report wish to celebrate and acknowledge all the fantastic achievements and inspiration accomplished by Prof. Inganas all since 1981.
|
|
2. |
- Bernacka Wojcik, Iwona, et al.
(författare)
-
Flexible Organic Electronic Ion Pump for Flow-Free Phytohormone Delivery into Vasculature of Intact Plants
- 2023
-
Ingår i: Advanced Science. - : WILEY. - 2198-3844. ; 10:14
-
Tidskriftsartikel (refereegranskat)abstract
- Plant vasculature transports molecules that play a crucial role in plant signaling including systemic responses and acclimation to diverse environmental conditions. Targeted controlled delivery of molecules to the vascular tissue can be a biomimetic way to induce long distance responses, providing a new tool for the fundamental studies and engineering of stress-tolerant plants. Here, a flexible organic electronic ion pump, an electrophoretic delivery device, for controlled delivery of phytohormones directly in plant vascular tissue is developed. The c-OEIP is based on polyimide-coated glass capillaries that significantly enhance the mechanical robustness of these microscale devices while being minimally disruptive for the plant. The polyelectrolyte channel is based on low-cost and commercially available precursors that can be photocured with blue light, establishing much cheaper and safer system than the state-of-the-art. To trigger OEIP-induced plant response, the phytohormone abscisic acid (ABA) in the petiole of intact Arabidopsis plants is delivered. ABA is one of the main phytohormones involved in plant stress responses and induces stomata closure under drought conditions to reduce water loss and prevent wilting. The OEIP-mediated ABA delivery triggered fast and long-lasting stomata closure far away from the delivery point demonstrating systemic vascular transport of the delivered ABA, verified delivering deuterium-labeled ABA.
|
|
3. |
- Blake, Jolie, 1986, et al.
(författare)
-
Scalable Reflective Plasmonic Structural Colors from Nanoparticles and Cavity Resonances – the Cyan-Magenta-Yellow Approach
- 2022
-
Ingår i: Advanced Optical Materials. - : Wiley. - 2195-1071 .- 2162-7568. ; 10:13
-
Tidskriftsartikel (refereegranskat)abstract
- Plasmonic metasurfaces for color generation are emerging as important components for next generation display devices. Fabricating bright plasmonic colors economically and via easily scalable methods, however, remains difficult. Here, the authors demonstrate an efficient and scalable strategy based on colloidal lithography to fabricate silver-based reflective metal–insulator–nanodisk plasmonic cavities that provide a cyan-magenta-yellow (CMY) color palette with high relative luminance. With the same basic structure, they exploit different mechanisms to efficiently produce a complete subtractive color palette. Finite-difference time-domain simulations reveal that these mechanisms include gap surface plasmon modes for thin insulators and hybridized modes between disk plasmons and Fabry–Pérot modes for thicker systems. To produce yellow hues, they take advantage of higher-energy gap surface plasmon modes to allow resonance dips in the blue spectral region for comparably large nanodisks, thereby circumventing difficult fabrication of nanodisks less than 80 nm. It is anticipated that incorporation of these strategies can reduce fabrication constraints, produce bright saturated colors, and expedite large-scale production.
|
|
4. |
- Borssén, Magnus, et al.
(författare)
-
DNA methylation holds prognostic information in relapsed precursor B-cell acute lymphoblastic leukemia
- 2018
-
Ingår i: Clinical Epigenetics. - : BIOMED CENTRAL LTD. - 1868-7083 .- 1868-7075. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Few biological markers are associated with survival after relapse of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). In pediatric T-cell ALL, we have identified promoter-associated methylation alterations that correlate with prognosis. Here, the prognostic relevance of CpG island methylation phenotype (CIMP) classification was investigated in pediatric BCP-ALL patients.Methods: Six hundred and one BCP-ALL samples from Nordic pediatric patients (age 1-18) were CIMP classified at initial diagnosis and analyzed in relation to clinical data.Results: Among the 137 patients that later relapsed, patients with a CIMP-profile (n = 42) at initial diagnosis had an inferior overall survival (pOS(5years) 33%) compared to CIMP+ patients (n = 95, pOS(5years) 65%) (p = 0.001), which remained significant in a Cox proportional hazards model including previously defined risk factors.Conclusion: CIMP classification is a strong candidate for improved risk stratification of relapsed BCP-ALL.
|
|
5. |
- Brooke, Robert, 1989-, et al.
(författare)
-
Greyscale and paper electrochromic polymer displays by UV patterning
- 2019
-
Ingår i: Polymers. - : MDPI AG. - 2073-4360. ; 11:2
-
Tidskriftsartikel (refereegranskat)abstract
- Electrochromic devices have important implications as smart windows for energy efficient buildings, internet of things devices, and in low-cost advertising applications. While inorganics have so far dominated the market, organic conductive polymers possess certain advantages such as high throughput and low temperature processing, faster switching, and superior optical memory. Here, we present organic electrochromic devices that can switch between two high-resolution images, based on UV-patterning and vapor phase polymerization of poly(3,4- ethylenedioxythiophene) films. We demonstrate that this technique can provide switchable greyscale images through the spatial control of a UV-light dose. The color space was able to be further altered via optimization of the oxidant concentration. Finally, we utilized a UV-patterning technique to produce functional paper with electrochromic patterns deposited on porous paper, allowing for environmentally friendly electrochromic displays.
|
|
6. |
- Brooke, Robert, et al.
(författare)
-
Infrared electrochromic conducting polymer devices
- 2017
-
Ingår i: Journal of Materials Chemistry C. - : The Royal Society of Chemistry. - 2050-7526 .- 2050-7534. ; 5:23, s. 5824-5830
-
Tidskriftsartikel (refereegranskat)abstract
- The conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is well known for its electrochromic properties in the visible region. Less focus has been devoted to the infrared (IR) wavelength range, although tunable IR properties could enable a wide range of novel applications. As an example, modern day vehicles have thermal cameras to identify pedestrians and animals in total darkness, but road and speed signs cannot be easily visualized by these imaging systems. IR electrochromism could enable a new generation of dynamic road signs that are compatible with thermal imaging, while simultaneously providing contrast also in the visible region. Here, we present the first metal-free flexible IR electrochromic devices, based on PEDOT:Tosylate as both the electrochromic material and electrodes. Lateral electrochromic devices enabled a detailed investigation of the IR electrochromism of thin PEDOT:Tosylate films, revealing large changes in their thermal signature, with effective temperature changes up to 10 [degree]C between the oxidized (1.5 V) and reduced (-1.5 V) states of the polymer. Larger scale (7 [times] 7 cm) vertical electrochromic devices demonstrate practical suitability and showed effective temperature changes of approximately 7 [degree]C, with good optical memory and fast switching (1.9 s from the oxidized state to the reduced state and 3.3 s for the reversed switching). The results are highly encouraging for using PEDOT:Tosylate for IR electrochromic applications.
|
|
7. |
- Brooke, Robert, 1989-, et al.
(författare)
-
Infrared electrochromic conducting polymer devices
- 2017
-
Ingår i: Journal of Materials Chemistry C. - : Royal Society of Chemistry (RSC). - 2050-7526 .- 2050-7534. ; 5:23, s. 5824-5830
-
Tidskriftsartikel (refereegranskat)abstract
- The conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is well known for its electrochromic properties in the visible region. Less focus has been devoted to the infrared (IR) wavelength range, although tunable IR properties could enable a wide range of novel applications. As an example, modern day vehicles have thermal cameras to identify pedestrians and animals in total darkness, but road and speed signs cannot be easily visualized by these imaging systems. IR electrochromism could enable a new generation of dynamic road signs that are compatible with thermal imaging, while simultaneously providing contrast also in the visible region. Here, we present the first metal-free flexible IR electrochromic devices, based on PEDOT:Tosylate as both the electrochromic material and electrodes. Lateral electrochromic devices enabled a detailed investigation of the IR electrochromism of thin PEDOT:Tosylate films, revealing large changes in their thermal signature, with effective temperature changes up to 10 °C between the oxidized (1.5 V) and reduced (-1.5 V) states of the polymer. Larger scale (7 × 7 cm) vertical electrochromic devices demonstrate practical suitability and showed effective temperature changes of approximately 7 °C, with good optical memory and fast switching (1.9 s from the oxidized state to the reduced state and 3.3 s for the reversed switching). The results are highly encouraging for using PEDOT:Tosylate for IR electrochromic applications.
|
|
8. |
- Che, Canyan, 1988-, et al.
(författare)
-
Twinning Lignosulfonate with a Conducting Polymer via Counter-Ion Exchange for Large-Scale Electrical Storage
- 2019
-
Ingår i: Advanced Sustainable Systems. - : Wiley-VCH Verlag. - 2366-7486. ; 3:9
-
Tidskriftsartikel (refereegranskat)abstract
- Lignosulfonate (LS) is a large-scale surplus product of the forest and paper industries, and has primarily been utilized as a low-cost plasticizer in making concrete for the construction industry. LS is an anionic redox-active polyelectrolyte and is a promising candidate to boost the charge capacity of the positive electrode (positrode) in redox-supercapacitors. Here, the physical-chemical investigation of how this biopolymer incorporates into the conducting polymer PEDOT matrix, of the positrode, by means of counter-ion exchange is reported. Upon successful incorporation, an optimal access to redox moieties is achieved, which provides a 63% increase of the resulting stored electrical charge by reversible redox interconversion. The effects of pH, ionic strength, and concentrations, of included components, on the polymer–polymer interactions are optimized to exploit the biopolymer-associated redox currents. Further, the explored LS-conducting polymer incorporation strategy, via aqueous synthesis, is evaluated in an up-scaling effort toward large-scale electrical energy storage technology. By using an up-scaled production protocol, integration of the biopolymer within the conducting polymer matrix by counter-ion exchange is confirmed and the PEDOT-LS synthesized through optimized strategy reaches an improved charge capacity of 44.6 mAh g−1.
|
|
9. |
- Chen, Shangzhi, et al.
(författare)
-
Redox-tunable structural colour images by UV-patterned conducting polymer nanofilms on metal surfaces
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Precise manipulation of light-matter interaction has enabled a wide variety of approaches to create bright and vivid structural colours. Techniques utilizing photonic crystals, Fabry-Pérot cavities, plasmonics, or high-refractive index dielectric metasurfaces have been studied for applications ranging from optical coatings to reflective displays. However, complicated fabrication procedures for sub-wavelength nanostructures, limited active areas, and inherent absence of tunability of these approaches significantly impede their further development towards flexible, large-scale, and switchable devices compatible with facile and cost-effective production. Herein, we present a simple and efficient method to generate structural colours based on nanoscale conducting polymer films prepared on metallic surfaces via vapour phase polymerization and ultraviolet (UV) light patterning. Varying the UV dose enables synergistic control of both nanoscale film thickness and polymer permittivity, which generates controllable colours from violet to red. Together with greyscale photomasks this enables fabrication of high-resolution colour images using single exposure steps. We further demonstrate spatiotemporal tuning of the structurally coloured surfaces and images via electrochemical modulation of the polymer redox state. The simple structure, facile fabrication, wide colour gamut, and dynamic colour tuning make this concept competitive for future multi-functional and smart displays.
|
|
10. |
- Chen, Shangzhi, et al.
(författare)
-
Tunable Structural Color Images by UV-Patterned Conducting Polymer Nanofilms on Metal Surfaces.
- 2021
-
Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 33:33
-
Tidskriftsartikel (refereegranskat)abstract
- Precise manipulation of light-matter interactions has enabled a wide variety of approaches to create bright and vivid structural colors. Techniques utilizing photonic crystals, Fabry-Pérot cavities, plasmonics, or high-refractive-index dielectric metasurfaces have been studied for applications ranging from optical coatings to reflective displays. However, complicated fabrication procedures for sub-wavelength nanostructures, limited active areas, and inherent absence of tunability of these approaches impede their further development toward flexible, large-scale, and switchable devices compatible with facile and cost-effective production. Here, a novel method is presented to generate structural color images based on monochromic conducting polymer films prepared on metallic surfaces via vapor phase polymerization and ultraviolet (UV) light patterning. Varying the UV dose enables synergistic control of both nanoscale film thickness and polymer permittivity, which generates controllable structural colors from violet to red. Together with grayscale photomasks this enables facile fabrication of high-resolution structural color images. Dynamic tuning of colored surfaces and images via electrochemical modulation of the polymer redox state is further demonstrated. The simple structure, facile fabrication, wide color gamut, and dynamic color tuning make this concept competitive for applications like multifunctional displays.
|
|
11. |
- Edman Jönsson, Gustav, 1983, et al.
(författare)
-
Solar Transparent Radiators by Optical Nanoantennas
- 2017
-
Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6984 .- 1530-6992. ; 17:11, s. 6766-6772
-
Tidskriftsartikel (refereegranskat)abstract
- Architectural windows are a major cause of thermal discomfort as the inner glazing during cold days can be several degrees colder than the indoor air. Mitigating this, the indoor temperature has to be increased, leading to unavoidable thermal losses. Here we present solar thermal surfaces based on complex nanoplasmonic antennas that can raise the temperature of window glazing by up to 8 K upon solar irradiation while transmitting light with a color rendering index of 98.76. The nanoantennas are directional, can be tuned to absorb in different spectral ranges, and possess a structural integrity that is not substrate-dependent, and thus they open up for application on a broad range of surfaces.
|
|
12. |
- Elhag, Sami, et al.
(författare)
-
Low-temperature growth of polyethylene glycol-doped BiZn2VO6 nanocompounds with enhanced photoelectrochemical properties
- 2017
-
Ingår i: Journal of Materials Chemistry A. - Cambridge : Royal Society of Chemistry. - 2050-7488. ; 5:3, s. 1112-1119
-
Tidskriftsartikel (refereegranskat)abstract
- We demonstrate scalable, low-cost and low-temperature (<100 °C) aqueous chemical growth of bismuth–zinc vanadate (BiZn2VO6) nanocompounds by BiVO4 growth on ZnO nanobelts (NBs). The nanocompounds were further doped with polyethylene glycol (PEG) to tune the electronic structure of the materials, as a means to lower the charge carrier recombination rate. The chemical composition, morphology, and detailed nanostructure of the BiZn2VO6 nanocompounds were characterized. They exhibit rice-like morphology, are highly dense on the substrate and possess a good crystalline quality. Photoelectrochemical characterization in 0.1 M lithium perchlorate in carbonate propylene shows that BiZn2VO6 nanocompounds are highly suitable as anodes for solar-driven photoelectrochemical applications, providing significantly better performance than with only ZnO NBs. This performance could be attributed to the heterogeneous catalysis effect at nanocompound and ZnO NB interfaces, which have enhanced the electron transfer process on the electrode surface. Furthermore, the charge collection efficiency could be significantly improved through PEG doping of nanocompounds. The photocurrent density of PEG-doped BiZn2VO6 nanocompounds reached values of 2 mA cm−2 at 1.23 V (vs. Ag/AgCl), over 60% larger than that of undoped BiZn2VO6 nanocompounds. Photoluminescence emission experiments confirmed that PEG plays a crucial role in lowering the charge carrier recombination rate. The presented BiZn2VO6 nanocompounds are shown to provide highly competitive performance compared with other state-of-the art photoelectrodes.
|
|
13. |
- Fan, Xing, 1975-, et al.
(författare)
-
Guaranteed real-time communication in packet-switched networks with FCFS queuing
- 2009
-
Ingår i: Computer Networks. - Amsterdam : North Holland. - 1389-1286 .- 1872-7069. ; 53:3, s. 400-417
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we propose a feasibility analysis of periodic hard real-time traffic in packet-switched networks using first come first served (FCFS) queuing but no traffic shapers. Our work constitutes a framework that can be adopted for real-time analysis of switched low-cost networks like Ethernet without modification of the standard network components. Our analysis is based on a flexible network and traffic model, e.g., variable-sized frames, arbitrary deadlines and multiple switches. The correctness of our real-time analysis and the tightness of it for network components in single-switch networks are given by theoretical proofs. The performance of the end-to-end real-time analysis is evaluated by simulations. Moreover, our conceptual and experimental comparison studies between our analysis and the commonly used Network Calculus (NC) shows that our analysis can achieve better performance than NC in many cases.
|
|
14. |
- Fan, Xing, 1975-, et al.
(författare)
-
Guaranteed Real-Time Communication in Packet-Switched Networks with FCFS queuing : Analysis and Simulations
- 2007
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In this report, we present a real-time analytical framework and the performance evaluation on our analysis. We propose a feasibility analysis of periodic hard real-time traffic in packet-switched networks using First Come First Served (FCFS) queuing but no traffic shapers. We choose switched Ethernet as an example to present the idea of our analysis and our experimental evaluations in this report.The remainder of the report is organized as follows. In Chapter 2, we define the network models, important concepts and terminology for real-time analysis. Chapter 3 presents our real-time analysis for isolated network elements. Chapter 4 gives end-to-end real-time analysis. Chapter 5 presents the performance evaluation of our results by simulation and comparison study and summarizes this report.
|
|
15. |
- Gamage, Sampath, et al.
(författare)
-
Reflective and transparent cellulose-based passive radiative coolers
- 2021
-
Ingår i: Cellulose. - : Springer. - 0969-0239 .- 1572-882X. ; 28, s. 9383-9393
-
Tidskriftsartikel (refereegranskat)abstract
- Radiative cooling passively removes heat from objects via emission of thermal radiation to cold space. Suitable radiative cooling materials absorb infrared light while they avoid solar heating by either reflecting or transmitting solar radiation, depending on the application. Here, we demonstrate a reflective radiative cooler and a transparent radiative cooler solely based on cellulose derivatives manufactured via electrospinning and casting, respectively. By modifying the microstructure of cellulose materials, we control the solar light interaction from highly reflective (> 90%, porous structure) to highly transparent (approximate to 90%, homogenous structure). Both cellulose materials show high thermal emissivity and minimal solar absorption, making them suitable for daytime radiative cooling. Used as coatings on silicon samples exposed to sun light at daytime, the reflective and transparent cellulose coolers could passively reduce sample temperatures by up to 15 degrees C and 5 degrees C, respectively.
|
|
16. |
- Gamage, Sampath, et al.
(författare)
-
Transparent nanocellulose metamaterial enables controlled optical diffusion and radiative cooling
- 2020
-
Ingår i: Journal of Materials Chemistry C. - : Royal Society of Chemistry. - 2050-7526 .- 2050-7534. ; 8:34, s. 11687-11694
-
Tidskriftsartikel (refereegranskat)abstract
- Materials that provide independent control of infrared thermal radiation and haze in the visible could benefit many areas and applications, including clothing, packaging and photovoltaics. Here, we study this possibility for a metamaterial composite paper based on cellulose nanofibrils (CNF) and silicon dioxide (SiO2) microparticles with infrared (IR) Fröhlich phonon resonances. This CNF-SiO2composite shows outstanding transparency in the visible wavelength range, with the option of controlling light diffusion and haze from almost zero to 90% by varying the SiO2microparticle concentration. We further show that the transparent metamaterial paper could maintain high thermal emissivity in the atmospheric IR window, as attributed to strong IR absorption of both the nanocellulose and the resonant SiO2microparticles. The high IR emissivity and low visible absorption make the paper suitable for passive radiative cooling and we demonstrate cooling of the paper to around 3 °C below ambient air temperature by exposing it to the sky.
|
|
17. |
- Gisladottir, Rosa S, et al.
(författare)
-
Sequence Variants in TAAR5 and Other Loci Affect Human Odor Perception and Naming.
- 2020
-
Ingår i: Current biology : CB. - : Elsevier BV. - 1879-0445 .- 0960-9822. ; 30:23
-
Tidskriftsartikel (refereegranskat)abstract
- Olfactory receptor (OR) genes in humans form a special class characterized by unusually high DNA sequence diversity, which should give rise to differences in perception and behavior. In the largest genome-wide association study to date based on olfactory testing, we investigated odor perception and naming with smell tasks performed by 9,122 Icelanders, with replication in a separate sample of 2,204 individuals. We discovered an association between a low-frequency missense variant in TAAR5 and reduced intensity rating of fish odor containing trimethylamine (p.Ser95Pro, pcombined= 5.6× 10-15). We demonstrate that TAAR5 genotype affects aversion to fish odor, reflected by linguistic descriptions of the odor and pleasantness ratings. We also discovered common sequence variants in two canonical olfactory receptor loci that associate with increased intensity and naming of licorice odor (trans-anethole: lead variant p.Lys233Asn in OR6C70, pcombined= 8.8× 10-16 and pcombined= 1.4× 10-9) and enhanced naming of cinnamon (trans-cinnamaldehyde; intergenic variant rs317787-T, pcombined= 5.0× 10-17). Together, our results show that TAAR5 genotype variation influences human odor responses and highlight that sequence diversity in canonical OR genes can lead to enhanced olfactory ability, in contrast to the view that greater tolerance for mutations in the human OR repertoire leads to diminished function.
|
|
18. |
- Gugole, Marika, 1993, et al.
(författare)
-
Electrochromic Inorganic Nanostructures with High Chromaticity and Superior Brightness
- 2021
-
Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6992 .- 1530-6984. ; 21:10, s. 4343-4350
-
Tidskriftsartikel (refereegranskat)abstract
- The possibility of actively controlling structural colors has recently attracted a lot of attention, in particular for new types of reflective displays (electronic paper). However, it has proven challenging to achieve good image quality in such devices, mainly because many subpixels are necessary and the semitransparent counter electrodes lower the total reflectance. Here we present an inorganic electrochromic nanostructure based on tungsten trioxide, gold, and a thin platinum mirror. The platinum reflector provides a wide color range and makes it possible to "reverse"the device design so that electrolyte and counter electrode can be placed behind the nanostructures with respect to the viewer. Importantly, this makes it possible to maintain high reflectance regardless of how the electrochemical cell is constructed. We show that our nanostructures clearly outperform the latest commercial color e-reader in terms of both color range and brightness.
|
|
19. |
- Johnsson, Helena, et al.
(författare)
-
En pedagogisk idé för ingenjörsutbildningarna vid Luleå tekniska universitet
- 2009
-
Konferensbidrag (refereegranskat)abstract
- Utmärkande för Luleå tekniska universitet (LTU) har länge varit närheten mellan studenterna och lärarna vilket har manifesterats genom klassrumsundervisning, lärartillgänglighet, mindre studiegrupper, koncentrerade campus etc. Undervisningsformerna har dock ändrats till att idag omfatta dels klassiska föreläsningar i stora studentgrupper, men också projektarbete i team där totalt sett 1/3 av all undervisning vid Luleå tekniska universitet sker i projektform. En fråga har ställts: Har Luleå tekniska universitet idag en gemensam pedagogisk idé för ingenjörsutbildningarna? I så fall är ytterligare en fråga hur denna pedagogiska idé tar sig uttryck i organisationen?Intervjuer med 40 aktiva lärare vid Luleå tekniska universitet har genomförts av projektgruppen (tillika författarna) varpå svaren har grupperats och analyserats i fjorton olika teman. Från dessa teman har sedan fyra hörnstenar i en definition av en pedagogisk idé aggregerats. Formuleringen av den pedagogiska idén lyder: Ett aktivt lärande för yrkeslivet – i branschnära projekt och med god vetenskaplig grund tränas förmågan att arbeta som ingenjör genom coachning från lärare i ett nära och öppet klimat. Idén har antagits av den tekniska fakultetsnämnden vid Luleå tekniska universitet och verifierats på institutionerna. Exempel på implementering och hur den pedagogiska idén aktivt verkar presenteras i artikeln.
|
|
20. |
- Jonsson, Bibi, et al.
(författare)
-
Dagmar Edqvist
- 2015
-
Ingår i: Malmö Nation 125 år. Nationens budbärare – en bok om framstående kulturpersonligheter. - 1101-4164. - 9789163793349 ; , s. 148-152
-
Bokkapitel (populärvet., debatt m.m.)
|
|
21. |
|
|
22. |
- Jonsson, Magnus, et al.
(författare)
-
Carotid Endarterectomy After Intracranial Endovascular Thrombectomy for Acute Ischaemic Stroke in Patients with Carotid Artery Stenosis
- 2022
-
Ingår i: European Journal of Vascular and Endovascular Surgery. - : Elsevier. - 1078-5884 .- 1532-2165. ; 63:3, s. 371-378
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: Recent randomised controlled trials demonstrated the benefit of intracranial endovascular thrombectomy (EVT) in acute ischaemic stroke. There is no consensus, however, on how to treat concomitant extracranial carotid artery stenosis after EVT. The aim of this study was to evaluate the outcome in patients treated with carotid endarterectomy (CEA) after EVT, comparing complication rates among patients undergoing CEA for stroke without previous EVT.Methods: This was a registry study of all patients (n = 3 780) treated with CEA after stroke in Sweden and the capital Helsinki region, Finland, from January 2011 to September 2020. Sixty three patients (1.7%; 0.5% 2011, 4.3% 2019) underwent EVT prior to CEA. The primary outcome was 30 day stroke and death rate.Results: The EVT+CEA group had major stroke as the qualifying neurological event (QNE) in 79%, but just 5.9% had this in the CEA only group (p < .001). Intravenous thrombolysis was administered before EVT in 54% of patients in the EVT+CEA group, but in just 12% in those receiving CEA only (p < .001). The combined stroke and death rate at 30 days for EVT+CEA was 0.0% (95% confidence interval [CI] 0.0 - 5.7). One patient had a post-operative TIA, none had post-operative intracerebral or surgical site haemorrhage. CEA was performed within a median of seven days (interquartile range 4, 15) after QNE, and 75% had CEA <= 14 days from QNE. The main reason to postpone CEA was an infarct larger than one third of the middle cerebral artery territory. The stroke and death rate in patients treated with CEA only was 3.7% (95% CI 3.2 - 4.4), CEA was performed a median of eight days after QNE, and in 79.7% in <= 14 days. The three year survival after EVT+CEA was 93% (95% CI 85 - 100), compared with 87% (95% CI 86 - 88) after CEA only. Cox regression analysis adjusting for age showed no increased all cause mortality after EVT+CEA (HR 1.3, 95% CI 0.6 - 2.7, p = .52).Conclusion: These results indicate that CEA is safe to perform after previous successful EVT for acute ischaemic stroke. Results were comparable with those undergoing CEA only, despite the EVT+CEA patients having more severe stroke symptoms prior to surgery, and timing was similar.
|
|
23. |
- Jonsson, Magnus, 1969-, et al.
(författare)
-
Dynamic time-deterministic traffic in a fiber-optic WDM star network
- 1997
-
Ingår i: Proceedings. - Piscataway, NJ. : IEEE Computer Society. - 0818680342 ; , s. 25-33
-
Konferensbidrag (refereegranskat)abstract
- A number of protocols for WDM (Wavelength Division Multiplexing) star networks have been proposed. However, the area of real-time protocols for these networks is quite unexplored. In this paper, a real-time protocol, based on TDM (Time Division Multiplexing), for fiber-optic star networks is presented. By the use of WDM, multiple Gb/s channels are achieved. Services for both guarantee-seeking messages and best-effort messages are supported for single destination, multicast, and broadcast transmission. Slot reserving can be used to increase the time-deterministic bandwidth, while still having an efficient bandwidth utilization due to a simple slot release method. The deterministic properties of the protocol are analyzed and simulation results presented. © 1997 IEEE
|
|
24. |
- Jonsson, Magnus P., et al.
(författare)
-
Simultaneous Nanoplasmonic and Quartz Crystal Microbalance Sensing: Analysis of Biomolecular Conformational Changes and Quantification of the Bound Molecular Mass
- 2008
-
Ingår i: Analytical Chemistry. - : American Chemical Society. - 0003-2700 .- 1520-6882. ; 80:21, s. 7988-7995
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents a study of supported lipid bilayer (SIB) formation and subsequent protein binding using a sensor that combines localized surface plasmon resonance (LSPR) and quartz crystal microbalance with dissipation (QCM-D) monitoring. The LSPR activity arises from silicon oxide (SiOx) coated nanometric apertures in a thin gold film, which also serves as the active electrode of a QCM-D crystal. Both transducer principles provide signatures for the formation of a SLB upon adsorption and subsequent rupture of adsorbed lipid vesicles. However, the two techniques are sensitive over different regions of the sample: LSPR primarily inside and on the rim of the holes and QCM-D primarily on the planar areas between the holes. Although the dimension of the lipid vesicles is on the same order as the dimension of the nanoholes, it is concluded from the response of the combined system that vesicle rupture in the nanoholes and on the planar region between the holes is synchronized. Furthermore, by determining the thickness of the SLB from the QCM-D response, the characteristic decay length of the LSPR field intensity could be determined. This made it possible not only to determine the mass and refractive index of the homogeneous SLB but also to postulate a generic means to quantify the LSPR response in terms of mass-uptake also for nonhomogeneous films. This is exemplified by measuring the adsorbed lipid mass during vesicle adsorption, yielding the critical lipid vesicle coverage at which spontaneous rupture into a planar bilayer occurs. The generic applicability and versatility of the method is demonstrated from specific protein binding to a functionalized SLB. From the absolute refractive index of the protein, provided from the LSPR data alone, it was possible to determine both the effective thickness of the protein film and the molecular mass (or number) of bound protein.
|
|
25. |
- Jonsson, Magnus, 1973-
(författare)
-
Thermally Expandable Microspheres Prepared via Suspension Polymerization - Synthesis, Characterization, and Application
- 2010
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Thermally expandable microspheres are polymeric core/shell particles in which a volatile hydrocarbon is encapsulated by a thermoplastic shell. When these microspheres are heated, they expand and increase their volume dramatically. This volume increase is retained upon cooling, leading to a density reduction from around 1100 kg m-3 to about 30 kg m-3. Since the development in the early 1970´s, microspheres have been used extensively by the industry as a foaming agent or light weight filler. In this thesis, microspheres with a poly(acrylonitrile-co-methacrylonitrile) shell have been synthesized through free radical suspension polymerization. The microspheres have been characterized with respect to particle morphology and expansion properties in order to deepen the understanding of the microspheres. It was found that the monomer feed ratio and the polymerization temperature are very important parameters with respect to the expansion properties. Excellent expansion could only be accomplished when polymerizing at 62 °C, with the acrylonitrile feed, fAN, being around 60 mol%, even though core/shell microspheres are formed over a much wider range of fAN. Furthermore, no expansion was achieved when polymerizing at 80 °C, even though no noticeable differences were found, compared to the corresponding sample polymerized at 62 °C. It was also shown that the expansion properties can be modified by replacing the encapsulated hydrocarbon by another hydrocarbon with a different boiling point. Not only is the boiling point important, the structure of the hydrocarbon is also important. Isooctane which is highly branched was found to give superior expansion compared to linear or cyclic hydrocarbons having a similar boiling point. Crosslinking of the polymer shell has proven to be very important for the expansion properties. Both the amount and the structure of the crosslinker are important parameters. Especially the maximum expansion can be improved by the crosslinking of the polymer shell. This originates in an increase in the shape persistence of the expanded microspheres at elevated temperatures. By the combination of crosslinkers that are incorporated separately into the polymer shell, the onset temperature of expansion can be increased significantly. Finally, the surface of microspheres has been modified by grafting poly(glycidyl methacrylate) from the surface by ARGET ATRP. Given that the reaction conditions are appropriate, such modifications can be performed with only limited effects on the expansion properties of the microspheres.
|
|
26. |
- Kim, Nara, 1985-, et al.
(författare)
-
Electric transport properties in PEDOT thin films
- 2019. - 4
-
Ingår i: Conjugated polymers. - Boca Raton : CRC Press. - 9780429190520 ; , s. 45-128
-
Bokkapitel (refereegranskat)abstract
- In this chapter, the authors summarize their understanding of Poly(3,4-ethylenedioxythiophene) (PEDOT), with respect to its chemical and physical fundamentals. They focus upon the structure of several PEDOT systems, from the angstrom level and up, and the impact on both electronic and ionic transport. The authors discuss the structural properties of PEDOT:X and PEDOT:poly(styrenesulfonate) based on experimental data probed at the scale ranging from angstrom to submicrometer. The morphology of PEDOT is influenced by the nature of counter-ions, especially at high oxidation levels. The doping anions intercalate between PEDOT chains to form a “sandwich” structure to screen the positive charges in PEDOT chains. The authors provide the main transport coefficients such as electrical conductivity s, Seebeck coefficient S, and Peltier coefficient σ, starting from a general thermodynamic consideration. The optical conductivity of PEDOT has also been examined based on the effective medium approximation, which is normally used to describe microscopic permittivity properties of composites made from several different constituents.
|
|
27. |
- Lee, Seunghyun, et al.
(författare)
-
Plasmonic polymer nanoantenna arrays for electrically tunable and electrode-free metasurfaces
- 2023
-
Ingår i: Journal of Materials Chemistry A. - : ROYAL SOC CHEMISTRY. - 2050-7488 .- 2050-7496. ; 11:40, s. 21569-21576
-
Tidskriftsartikel (refereegranskat)abstract
- Electrically tunable metasurfaces and interrelated nanofabrication techniques are essential for metasurface-based optoelectronic applications. We present a nanofabrication method suitable for various types of plasmonic polymer metasurfaces including inverted arrays of nanoantennas. Inverted metasurfaces are of particular interest since the metasurface itself can work as an electrode due to its interconnected nature, which enables electrical control without adopting an additional electrode. In comparison with inverted nanodisk arrays that support relatively weak resonance features, we show that inverted nanorod arrays can possess stronger resonances, even comparable with those of nanorod arrays. The origin of plasmon resonances in inverted arrays is systematically investigated using finite-difference time-domain (FDTD) simulations. Further, we demonstrate electrically tunable electrode-free metasurface devices using polymer inverted nanorod arrays, which can operate in the full spectral range of the material including the mid-infrared region. Electrically tunable and electrode-free metasurfaces using plasmonic polymer inverted nanoantenna arrays can operate across the entire spectral range of the material, including the mid-infrared region.
|
|
28. |
- Leion, Felicia, et al.
(författare)
-
Estimating glomerular filtration rate (GFR) in children. The average between a cystatin C- and a creatinine-based equation improves estimation of GFR in both children and adults and enables diagnosing Shrunken Pore Syndrome.
- 2017
-
Ingår i: Scandinavian Journal of Clinical and Laboratory Investigation. - : Informa UK Limited. - 0036-5513 .- 1502-7686. ; 77:5, s. 338-344
-
Tidskriftsartikel (refereegranskat)abstract
- Estimating glomerular filtration rate (GFR) in adults by using the average of values obtained by a cystatin C- (eGFRcystatin C) and a creatinine-based (eGFRcreatinine) equation shows at least the same diagnostic performance as GFR estimates obtained by equations using only one of these analytes or by complex equations using both analytes. Comparison of eGFRcystatin C and eGFRcreatinine plays a pivotal role in the diagnosis of Shrunken Pore Syndrome, where low eGFRcystatin C compared to eGFRcreatinine has been associated with higher mortality in adults. The present study was undertaken to elucidate if this concept can also be applied in children. Using iohexol and inulin clearance as gold standard in 702 children, we studied the diagnostic performance of 10 creatinine-based, 5 cystatin C-based and 3 combined cystatin C-creatinine eGFR equations and compared them to the result of the average of 9 pairs of a eGFRcystatin C and a eGFRcreatinine estimate. While creatinine-based GFR estimations are unsuitable in children unless calibrated in a pediatric or mixed pediatric-adult population, cystatin C-based estimations in general performed well in children. The average of a suitable creatinine-based and a cystatin C-based equation generally displayed a better diagnostic performance than estimates obtained by equations using only one of these analytes or by complex equations using both analytes. Comparing eGFRcystatin and eGFRcreatinine may help identify pediatric patients with Shrunken Pore Syndrome.
|
|
29. |
- Malti, Abdellah, et al.
(författare)
-
Freestanding electrochromic paper
- 2016
-
Ingår i: Journal of Materials Chemistry C. - : Royal Society of Chemistry (RSC). - 2050-7526 .- 2050-7534. ; 4:41, s. 9680-9686
-
Tidskriftsartikel (refereegranskat)abstract
- Electrochromic displays based on conducting polymers exhibit higher contrasts and are cheaper, faster, more durable, and easier to synthesize as well as to process than their non-polymeric counterparts. However, current devices are typically based on thin electrochromic layers on top of a reflecting surface, which limits the thickness of the polymer layer to a few hundred nanometers. Here, we embed a light-scattering material within the electrochromic material to achieve a freestanding electrochromic paper-like electrode (50 to 500 μm). The device is based on a cellulose composite combining PEDOT:PSS as the electrochromic material and TiO2 nanoparticles as the reflecting material. Owing to the excellent refractive properties of TiO2, this nanocomposite is white in the neutral state and, when reduced, turns blue resulting in a color contrast around 30. The composite has a granular morphology and, as shown by AFM, an intermingling of TiO2 and PEDOT:PSS at the surface. Variation of the amount of TiO2 within the composite material is shown to result in a trade-off in optical and electrical properties. A proof-of-concept freestanding electrochromic device was fabricated by casting all layers successively to maximize the interlayer conformation. This freestanding device was found to be stable for over 100 cycles when ramped between 3 and -3 V.
|
|
30. |
- Mitraka, Evangelia, 1986-
(författare)
-
Conducting Polymer Electrodes for Oxygen Reduction Reaction
- 2018
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Both the pollution level of the environment and the increasing energy demands have stimulated intense research on the development of low-cost environmentally-friendly energy conversion and storage systems with high efficiency, such as metal-air batteries and fuel cells.One of the most essential parts of both fuel cells and metal–air batteries is the air-electrode which is responsible for the reduction of O2. The air-electrode can use O2 from air facilitating the layout of the device; however, the process taking place on it is significantly complex. Currently, platinum (Pt) is the benchmark for air-electrodes in such technologies, although it is expensive and exhibits other important disadvantages which diminish the fuel cell performance. Therefore, extensive research has been devoted to reduce the amount of Pt used in air-electrodes and to develop a noble metal-free version of these electrodes.The area of printed electronics could facilitate the development of low-cost electrodes produced in high volume for such applications. Conducting polymers are attractive materials for this technology because they may combine several desired properties, like electronic conduction, ionic conduction and catalysis of electrochemical reactions.Among other conducting polymers, poly(3,4-ethylenedioxythiophene) (PEDOT) emerged as an alternative cathode catalyst material to Pt, due to its ability to effectively catalyze the oxygen reduction reaction (ORR), while it also exhibits high electrical and ionic conductivity.The focus of this thesis is to study the electrocatalytic activity and mechanism of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) when employed as an airelectrode in energy storage devices, such as fuel cells and metal-air batteries. Although PEDOT is extensively studied during the last decade as an air-electrode for fuel cell and metal-air batteries, vital pieces of the catalytic mechanism that PEDOT follows remain unknown, namely: (i) the sites of PEDOT on which O2 interacts and (ii) the intermediate species which are formed during the ORR. The content of this thesis tackles these topics, both from experimental and theoretical point of view. Moreover, it investigates the use of PEDOT as an active electrocatalyst in a polymer exchange membrane (PEM) fuel cell, by embedding the polymer in a cellulose matrix, aiming to fabricate a gas diffusion electrode for the ORR side of the device. Finally, the goal of the thesis surpasses the limit of the p-doped PEDOT and undertakes the evaluation of a n-type conjugated polymer of high electron affinity as a cathode in reduction processes.
|
|
31. |
- Mitraka, Evangelia, et al.
(författare)
-
Oxygen-induced doping on reduced PEDOT
- 2017
-
Ingår i: Journal of Materials Chemistry A. - : ROYAL SOC CHEMISTRY. - 2050-7488 .- 2050-7496. ; 5:9, s. 4404-4412
-
Tidskriftsartikel (refereegranskat)abstract
- The conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) has shown promise as air electrode in renewable energy technologies like metal-air batteries and fuel cells. PEDOT is based on atomic elements of high abundance and is synthesized at low temperature from solution. The mechanism of oxygen reduction reaction (ORR) over chemically polymerized PEDOT: Cl still remains controversial with eventual role of transition metal impurities. However, regardless of the mechanistic route, we here demonstrate yet another key active role of PEDOT in the ORR mechanism. Our study demonstrates the decoupling of conductivity (intrinsic property) from electrocatalysis (as an extrinsic phenomenon) yielding the evidence of doping of the polymer by oxygen during ORR. Hence, the PEDOT electrode is electrochemically reduced (undoped) in the voltage range of ORR regime, but O-2 keeps it conducting; ensuring PEDOT to act as an electrode for the ORR. The interaction of oxygen with the polymer electrode is investigated with a battery of spectroscopic techniques.
|
|
32. |
- Mitraka, Evangelia, et al.
(författare)
-
PEDOT-Cellulose Gas Diffusion Electrodes for Disposable Fuel Cells
- 2019
-
Ingår i: Advanced Sustainable Systems. - : Wiley-VCH Verlag. - 2366-7486. ; 3:12
-
Tidskriftsartikel (refereegranskat)abstract
- The mass implementation of renewable energy sources is limited by the lack of energy storage solutions operating on various timescales. Electrochemical technologies such as supercapacitors and batteries cannot handle long storage time because of self-discharge issues. The combination of fuel storage technology and fuel cells is an attractive solution for long storage times. In that context, large-scale fuel cell solutions are required for massive energy storage in cities, which leads to possible concepts such as low-cost disposable fully organic membrane assemblies in fuel cells to avoid regeneration of expensive poisoned electrodes. Here, the formation of an organic gas diffusion electrode (GDE) fabricated by paper-making production, combined with in situ polymerization is demonstrated for the first time. Cellulose is used as a 3D scaffold functionalized with poly(3,4-ethylenedioxythiophene) (PEDOT) serving as both an electrical conductor and an electrocatalyst of high efficiency for the oxygen reduction reaction. The PEDOT-cellulose porous GDE is implemented in a membrane assembly and demonstrated in a H2-O2 fuel cell. The demonstration of low-cost material/manufacturing that is environmentally friendly is a paradigm shift in the development of fuel cells for a sustainable society.
|
|
33. |
- Morian, Hanna, et al.
(författare)
-
Reliability and validity testing of team emergency assessment measure in a distributed team context
- 2023
-
Ingår i: Frontiers in Psychology. - 1664-1078. ; 14
-
Tidskriftsartikel (refereegranskat)abstract
- Medical multi-professional teams are increasingly collaborating via telemedicine. In distributed team settings, members are geographically separated and collaborate through technology. Developing improved training strategies for distributed teams and finding appropriate instruments to assess team performance is necessary. The Team Emergency Assessment Measure (TEAM), an instrument validated in traditional collocated acute-care settings, was tested for validity and reliability in this study when used for distributed teams. Three raters assessed video recordings of simulated team training scenarios (n = 18) among teams with varying levels of proficiency working with a remotely located physician via telemedicine. Inter-rater reliability, determined by intraclass correlation, was 0.74-0.92 on the TEAM instrument's three domains of leadership, teamwork, and task management. Internal consistency (Cronbach's alpha) ranged between 0.89-0.97 for the various domains. Predictive validity was established by comparing scores with proficiency levels. Finally, concurrent validity was established by high correlations, >0.92, between scores in the three TEAM domains and the teams' overall performance. Our results indicate that TEAM can be used in distributed acute-care team settings and consequently applied in future-directed learning and research on distributed healthcare teams.
|
|
34. |
|
|
35. |
- Sandberg, Mats, et al.
(författare)
-
Photoconductive zinc oxide-composite paper by pilot paper machine manufacturing
- 2016
-
Ingår i: Flexible and Printed Electronics. - : IOP Publishing. - 2058-8585. ; 1
-
Tidskriftsartikel (refereegranskat)abstract
- Smartmaterials can be used for awide variety of applications, including sensing and energy harvesting.Implementation of smartmaterials in large area devices requires scalablemanufacturing. The use ofpaper-making techniques would offer an enormous production capacity, allowing for low-cost andlarge-scalemanufacturing. In thisworkwe present a successful pilot scale papermachinemanufacturingof functional composite papers(100mmin−1 with aweb width of 30 cm) based on cellulose fibres andcommercial tetrapodal zinc oxidemicrowhiskers(ZnO-Ts).Carbon electrodes could successfully beprinted on the paper to form complete electronic devices where the paper itself is the active material.Thisenabled development of aZnO-composite paper photosensor,where we characterized its stability,sensitivity and speed. The devices show excellent photosensing properties over awide range of lightirradiances(0.01–1Sun), including short response times (∼10 s) and long-term stability. Under simulatedsunlight and a bias voltage of 1 V, small(0.5 cm2) two-probe interdigitated photosensor devices provided12μAphotocurrent.Under the same conditions, four-probe measurements of the composite papershowed a sheet resistance of 6.9·107Ω/sq. Four-probe measurements also demonstrated that the paperconductivity varies linearlywith light irradiance. To the best of ourknowledge, this is thefirst example ofpilot paper machine production of an optoelectronic paper, demonstrating the potential for large-scalepapermanufacturing of active smart paper from low-cost industrial bulk materials.
|
|
36. |
- Shiran Chaharsoughi, Mina, 1986-, et al.
(författare)
-
Hybrid Plasmonic and Pyroelectric Harvesting of Light Fluctuations
- 2018
-
Ingår i: Advanced Optical Materials. - : Wiley-Blackwell. - 2162-7568 .- 2195-1071.
-
Tidskriftsartikel (refereegranskat)abstract
- State-of-the-art solar energy harvesting systems based on photovoltaic technology require constant illumination for optimal operation. However, weather conditions and solar illumination tend to fluctuate. Here, a device is presented that extracts electrical energy from such light fluctuations. The concept combines light-induced heating of gold nanodisks (acting as plasmonic optical nanoantennas), and an organic pyroelectric copolymer film (poly(vinylidenefluoride-co-trifluoroethylene)), that converts temperature changes into electrical signals. This hybrid device can repeatedly generate current pulses, not only upon the onset of illumination, but also when illumination is blocked. Detailed characterization highlights the key role of the polarization state of the copolymer, while the copolymer thickness has minor influence on performance. The results are fully consistent with plasmon-assisted pyroelectric effects, as corroborated by combined optical and thermal simulations that match the experimental results. Owing to the tunability of plasmonic resonances, the presented concept is compatible with harvesting near infrared light while concurrently maintaining visible transparency.
|
|
37. |
- Sjögren, Magnus, et al.
(författare)
-
Cognition-enhancing effect of vagus nerve stimulation in patients with Alzheimer's disease: a pilot study.
- 2002
-
Ingår i: The Journal of clinical psychiatry. - 0160-6689. ; 63:11, s. 972-80
-
Tidskriftsartikel (refereegranskat)abstract
- Vagus nerve stimulation (VNS) is an established treatment method for therapy-refractory epilepsy and, in Europe, for treatment-resistant depression also. Clinical and experimental investigations have also shown positive effects of VNS on cognition in epilepsy and depression. The purpose of the present pilot study was to investigate the effect of VNS on cognition in patients with Alzheimer's disease.
|
|
38. |
- Stavrinidou, Eleni, et al.
(författare)
-
In vivo polymerization and manufacturing of wires and supercapacitors in plants
- 2017
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 114:11, s. 2807-2812
-
Tidskriftsartikel (refereegranskat)abstract
- Electronic plants, e-Plants, are an organic bioelectronic platform that allows electronic interfacing with plants. Recently we have demonstrated plants with augmented electronic functionality. Using the vascular system and organs of a plant, we manufactured organic electronic devices and circuits in vivo, leveraging the internal structure and physiology of the plant as the template, and an integral part of the devices. However, this electronic functionality was only achieved in localized regions, whereas new electronic materials that could be distributed to every part of the plant would provide versatility in device and circuit fabrication and create possibilities for new device concepts. Here we report the synthesis of such a conjugated oligomer that can be distributed and form longer oligomers and polymer in every part of the xylem vascular tissue of a Rosa floribunda cutting, forming long-range conducting wires. The plant’s structure acts as a physical template, whereas the plant’s biochemical response mechanism acts as the catalyst for polymerization. In addition, the oligomer can cross through the veins and enter the apoplastic space in the leaves. Finally, using the plant’s natural architecture we manufacture supercapacitors along the stem. Our results are preludes to autonomous energy systems integrated within plants and distribute interconnected sensor-actuator systems for plant control and optimization
|
|
39. |
- Sällman Almén, Markus, et al.
(författare)
-
Shrunken Pore Syndrome Is Associated With Increased Levels of Atherosclerosis-Promoting Proteins
- 2019
-
Ingår i: Kidney International Reports. - : Elsevier BV. - 2468-0249. ; 4:1, s. 67-79
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: Shrunken pore syndrome (SPS), originally defined by cystatin C-based estimated glomerular filtration rate (eGFRcystatin C) being less than 60% of creatinine-based estimated glomerular filtration rate (eGFRcreatinine) in the absence of extrarenal influences on the plasma levels of cystatin C or creatinine, is associated with a high increase in mortality, even in the absence of reduced glomerular filtration rate (GFR). The objective of the present study was to determine whether the proteome of patients with SPS shows differences from that of patients with normal or reduced measured GFR (mGFR) without SPS.Methods: Four patient cohorts were included: 1 cohort with normal mGFR without SPS, 1 with normal mGFR with SPS, 1 with reduced mGFR without SPS, and 1 with reduced mGFR with SPS. The plasma levels of 177 selected proteins were analyzed.Results: Differences in the levels of 30 proteins were specific for SPS; 31 differences were specific for patients with both SPS and reduced mGFR; and 27 were specific for reduced mGFR. Eighteen of the differences specific for SPS concerned proteins described as promoting, or being associated with, atherosclerosis. Twelve of the differences specific for patients with both SPS and reduced mGFR and 10 of the differences specific for reduced mGFR also concerned proteins described as promoting, or being associated with, atherosclerosis. Almost all (82 of 88) of the concentration differences represented increased levels. For SPS, but not for reduced mGFR, a correlation between protein size and increase in level was observed, with smaller proteins being associated with higher levels.Conclusion: The high mortality in shrunken pore syndrome might be caused by the accumulation of atherosclerosis-promoting proteins in this condition.
|
|
40. |
- Teni, F. S., et al.
(författare)
-
Variations in Patients' Overall Assessment of Their Health Across and Within Disease Groups Using the EQ-5D Questionnaire: Protocol for a Longitudinal Study in the Swedish National Quality Registers
- 2021
-
Ingår i: Jmir Research Protocols. - Toronto, ON, Canada : JMIR Publications Inc.. - 1929-0748. ; 10:8
-
Tidskriftsartikel (refereegranskat)abstract
- Background: EQ-5D is one of the most commonly used questionnaires to measure health-related quality of life. It is included in many of the Swedish National Quality Registers (NQRs). EQ-5D health states are usually summarized using "values" obtained from members of the general public, a majority of whom are healthy. However, an alternative, which remains to be studied in detail, is the potential to use patients' self-reported overall health on the visual analog scale (VAS) as a means of capturing experience-based perspective. Objective: The aim of this study is to assess EQ VAS as a valuation method with an experience-based perspective through comparison of its performance across and within patient groups, and with that of the general population in Sweden. Methods: Data on nearly 700,000 patients from 12 NQRs covering a variety of diseases/conditions and nearly 50,000 individuals from the general population will be analyzed. The EQ-5D-3L data from the 12 registers and EQ-5D-5L data from 2 registers will be used in the analyses. Longitudinal studies of patient-reported outcomes among different patient groups will be conducted in the period from baseline to 1-year follow-up. Descriptive statistics and analyses comparing EQ-5D dimensions and observed self-assessed EQ VAS values across and within patient groups will be performed. Comparisons of the change in health state and observed EQ VAS values at 1-year follow-up will also be undertaken. Regression models will be used to assess whether EQ-5D dimensions predict observed EQ VAS values to investigate patient value sets in each patient group. These will be compared across the patient groups and with the existing Swedish experience-based VAS and time trade-off value sets obtained from the general population. Results: Data retrieval started in May 2019 and data of patients in the 12 NQRs and from the survey conducted among the general population have been retrieved. Data analysis is ongoing on the retrieved data. Conclusions: This research project will provide information on the differences across and within patient groups in terms of self-reported health status through EQ VAS and comparison with the general population. The findings of the study will contribute to the literature by exploring the potential of self-assessed EQ VAS values to develop value sets using an experience-based perspective.
|
|
41. |
- Wang, Hui, et al.
(författare)
-
Ionic Thermoelectric Figure of Merit for Charging of Supercapacitors
- 2017
-
Ingår i: Advanced Electronic Materials. - : WILEY. - 2199-160X. ; 3:4
-
Tidskriftsartikel (refereegranskat)abstract
- Thermoelectric materials enable conversion of heat to electrical energy. The performance of electronic thermoelectric materials is typically evaluated using a figure of merit ZT = sigma alpha 2T/lambda, where sigma is the conductivity, alpha is the so-called Seebeck coefficient, and lambda is the thermal conductivity. However, it has been unclear how to best evaluate the performance of ionic thermoelectric materials, like ionic solids and electrolytes. These systems cannot be directly used in a traditional thermoelectric generator, because they are based on ions that cannot pass the interface between the thermoelectric material and external metal electrodes. Instead, energy can be harvested from the ionic thermoelectric effect by charging a supercapacitor. In this study, the authors investigate the ionic thermoelectric properties at varied relative humidity for the polyelectrolyte polystyrene sulfonate sodium and correlate these properties with the charging efficiency when used in an ionic thermoelectric supercapacitor (ITESC). In analogy with electronic thermoelectric generators, the results show that the charging efficiency of the ITESC can be quantitatively related to the figure of merit ZT(i) = sigma i alpha i2T/lambda. This means that the performance of ionic thermoelectric materials can also be compared and predicted based on the ZT, which will be highly valuable in the design of high-performance ITESCs.
|
|
42. |
- Welen, Karin, et al.
(författare)
-
COVIDENZA - A prospective, multicenter, randomized PHASE II clinical trial of enzalutamide treatment to decrease the morbidity in patients with Corona virus disease 2019 (COVID-19): a structured summary of a study protocol for a randomised controlled trial.
- 2021
-
Ingår i: Trials. - : Springer Science and Business Media LLC. - 1745-6215. ; 22:1
-
Tidskriftsartikel (refereegranskat)abstract
- The main goal of the COVIDENZA trial is to evaluate if inhibition of testosterone signalling by enzalutamide can improve the outcome of patients hospitalised for COVID-19. The hypothesis is based on the observation that the majority of patients in need of intensive care are male, and the connection between androgen receptor signalling and expression of TMPRSS2, an enzyme important for SARS-CoV-2 host cell internalization.Hospitalised COVID-19 patients will be randomised (2:1) to enzalutamide plus standard of care vs. standard of care designed to identify superiority.Included participants, men or women above 50 years of age, must be hospitalised for PCR confirmed COVID-19 symptoms and not in need of immediate mechanical ventilation. Major exclusion criteria are breast-feeding or pregnant women, hormonal treatment for prostate or breast cancer, treatment with immunosuppressive drugs, current symptomatic unstable cardiovascular disease (see Additional file 1 for further details). The trial is registered at Umeå University Hospital, Region Västerbotten, Sweden and 8 hospitals are approved for inclusion in Sweden.Patients randomised to the treatment arm will be treated orally with 160 mg (4x40 mg) enzalutamide (Xtandi®) daily, for five consecutive days. The study is not placebo controlled. The comparator is standard of care treatment for patients hospitalised with COVID-19.The primary endpoints of the study are (time to) need of mechanical ventilation or discharge from hospital as assessed by a clinical 7-point ordinal scale (up to 30 days after inclusion).Randomisation was stratified by center and sex. Each strata was randomized separately with block size six with a 2:1 allocation ratio (enzalutamide + "standard of care": "standard of care"). The randomisation list, with consecutive subject numbers, was generated by an independent statistician using the PROC PLAN procedure of SAS version 9.4 software (SAS Institute, Inc, Cary, North Carolina) BLINDING (MASKING): This is an open-label trial.The trial is designed to have three phases. The first, an exploration phase of 45 participants (30 treatment and 15 control) will focus on safety and includes a more extensive laboratory assessment as well as more frequent safety evaluation. The second prolongation phase, includes the first 100 participants followed by an interim analysis to define the power of the study. The third phase is the continuation of the study up to maximum 600 participants included in total.The current protocol version is COVIDENZA v2.0 as of September 10, 2020. Recruitment started July 29, 2020 and is presently in safety pause after the first exploration phase. Recruitment is anticipated to be complete by 31 December 2021.Eudract number 2020-002027-10 ClinicalTrials.gov Identifier: NCT04475601 , registered June 8, 2020 FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.
|
|
43. |
- Xiong, Kunli, 1987, et al.
(författare)
-
Switchable Plasmonic Metasurfaces with High Chromaticity Containing only Abundant Metals
- 2017
-
Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6984 .- 1530-6992. ; 17:11, s. 7033-7039
-
Tidskriftsartikel (refereegranskat)abstract
- Plasmonic color generation offers several advantages but is also limited by the cost and availability of noble metals like gold. In this work, we present color-tunable metasurfaces with high chromaticity and reflectivity consisting of an aluminum mirror, a dielectric spacer, and a plasmonic nanohole array in copper. Copper is shown to be an excellent alternative to gold when properly protected from oxidation and makes it possible to generate a wide RGB gamut covering 27% of the standard RGB. By patterning the metasurfaces into microscale pixel triplets, color photos can be well reproduced with high resolution over wafer-sized areas. Further, we demonstrate active modulation of the reflected intensity using an electrochromic conductive polymer deposited on top of the nanostructures by screen printing. This technology opens up for ultrathin and flexible reflective displays in full color, that is, plasmonic electronic paper, compatible with large-scale sustainable production.
|
|
44. |
- Zhao, Dan, et al.
(författare)
-
Ionic thermoelectric supercapacitors
- 2016
-
Ingår i: Energy & Environmental Science. - : ROYAL SOC CHEMISTRY. - 1754-5692 .- 1754-5706. ; 9:4, s. 1450-1457
-
Tidskriftsartikel (refereegranskat)abstract
- Temperature gradients are generated by the sun and a vast array of technologies and can induce molecular concentration gradients in solutions via thermodiffusion (Soret effect). For ions, this leads to a thermovoltage that is determined by the thermal gradient Delta T across the electrolyte, together with the ionic Seebeck coefficient alpha(i). So far, redox-free electrolytes have been poorly explored in thermoelectric applications due to a lack of strategies to harvest the energy from the Soret effect. Here, we report the conversion of heat into stored charge via a remarkably strong ionic Soret effect in a polymeric electrolyte (Seebeck coefficients as high as alpha(i) = 10 mV K-1). The ionic thermoelectric supercapacitor (ITESC) is charged under a temperature gradient. After the temperature gradient is removed, the stored electrical energy can be delivered to an external circuit. This new means to harvest energy is particularly suitable for intermittent heat sources like the sun. We show that the stored electrical energy of the ITESC is proportional to (Delta T alpha(i))(2). The resulting ITESC can convert and store several thousand times more energy compared with a traditional thermoelectric generator connected in series with a supercapacitor.
|
|
45. |
- Åkesson, Anna, et al.
(författare)
-
Shrunken pore syndrome and mortality : a cohort study of patients with measured GFR and known comorbidities
- 2020
-
Ingår i: Scandinavian Journal of Clinical and Laboratory Investigation. - : Informa UK Limited. - 1502-7686 .- 0036-5513. ; 80:5, s. 412-422
-
Tidskriftsartikel (refereegranskat)abstract
- Shrunken pore syndrome (SPS) is defined by a cystatin C-based estimation of glomerular filtration rate (eGFRCYS) being less than 60% or 70% of a creatinine-based GFR estimation (eGFRCR) in the absence of extrarenal influences on cystatin C or creatinine concentrations. SPS has been associated with a substantial increase in mortality or morbidity in all investigated populations. However, in these studies, neither the diagnoses, nor causes of death were described, and only estimated GFR was available. The present study concerns 2781 individuals with measured GFR (mGFR), known diagnoses, and known causes of death during 5.6 years in median. Cox multivariate proportional hazards regression model was used to estimate hazard ratios (HR) for all-cause and cancer, cardiovascular, diabetes or chronic kidney disease (CKD) as cause-specific mortality among patients with SPS. At an eGFRCYS/eGFRCR-ratio <0.70, the adjusted SPS death risk in the total cohort (HR 3.0, 95% CI 2.4-3.7) was clearly higher than that for the other diagnosis groups. In a sub-cohort of 1300 persons with or without diagnosis, but with normal mGFR, the all-cause mortality of SPS was markedly increased (HR 4.1, 95% CI 2.6-6.5). In a sub-cohort of 567 persons with normal mGFR and no diagnosis, the all-cause mortality of SPS was even more increased (HR 7.3, 95% CI 2.3-23). The prevalence of SPS in the total cohort was 23% and in the sub-cohorts 17 and 12%, respectively. As SPS is associated with a high mortality, occurs in the absence of reduced mGFR and albuminuria, it expands the spectrum of kidney disorders.
|
|
46. |
- Abdulla, Parosh, Professor, 1961-, et al.
(författare)
-
Optimal stateless model checking for reads-from equivalence under sequential consistency
- 2019
-
Ingår i: Proceedings of the ACM on Programming Languages. - : Association for Computing Machinery (ACM). - 2475-1421.
-
Tidskriftsartikel (refereegranskat)abstract
- We present a new approach for stateless model checking (SMC) of multithreaded programs under Sequential Consistency (SC) semantics. To combat state-space explosion, SMC is often equipped with a partial-order reduction technique, which defines an equivalence on executions, and only needs to explore one execution in each equivalence class. Recently, it has been observed that the commonly used equivalence of Mazurkiewicz traces can be coarsened but still cover all program crashes and assertion violations. However, for this coarser equivalence, which preserves only the reads-from relation from writes to reads, there is no SMC algorithm which is (i) optimal in the sense that it explores precisely one execution in each reads-from equivalence class, and (ii) efficient in the sense that it spends polynomial effort per class. \end{inparaenum} We present the first SMC algorithm for SC that is both optimal and efficient in practice, meaning that it spends polynomial time per equivalence class on all programs that we have tried. This is achieved by a novel test that checks whether a given reads-from relation can arise in some execution. Our experimental results show that Nidhugg/rfsc, although slower than the fastest SMC tools in programs where tools happen to examine the same number of executions, always scales similarly or better than them, and outperforms them by an exponential factor in programs where the reads-from equivalence is coarser than the standard one. We also present two non-trivial use cases where the new equivalence is particularly effective, as well as the significant performance advantage that Nidhugg/rfsc offers compared to state-of-the-art SMC and systematic concurrency testing tools.
|
|
47. |
|
|
48. |
|
|
49. |
- Adelswärd, Rebecka Millhagen
(författare)
-
Monument, minne, museum : Stockholms slott under det långa 1900-talet
- 2021
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This study examines how the Royal Palace of Stockholm gradually, from 1880–2000, became established as a monument in art and cultural history, as well as a site of national heritage. The musealisation process of the royal residence is described by analysing the origin of new museal and exhibition milieus, and changes in the palace’s State and Bernadotte Apartments. These measures were taken to enhance and manage this cultural heritage and to make it accessible by using art historical and antiquarian expertise. The thesis discusses the origins of the Palace Museum (1936), Gustav III’s Museum of Antiquities (1958, 1992), the Treasury (1970), the Royal Armoury (1978) and the Tre Kronor Museum (1999). Two periods of consolidation are discernible. First, the façade restoration of 1898–1902, during the reign of king Oskar II, and the completion of the sculpture programme make manifest the late 19th- century positioning of the Tessin palace as a national heritage site. With the appointment of the art historian John Böttiger as Surveyor of the Royal Collections, the king’s commitment to the royal collections led to both object-based scientific research and new conservation practices. Second, collection and exhibition activities evolved during the reign of king Gustaf VI Adolf, 1950–1973, with pronounced educational ambitions and democratic characteristics. The study illuminates the contributions of the palace architects, the role of the Office of the Governor of the Royal Palace and the relationship with the state-run Nationalmuseum and Royal Armoury, which have contributed to continuity in the presentation of historic collections. The thesis demonstrates the importance of art history writing for museal and restoration practices, particularly Stockholms slotts historia 1–3 (1940–1941), a publication decisive in the restoration work in the State and Bernadotte Apartments from the 1940s until the 1970s. The study examines the palace’s dual function as a national monument and royal residence, and how this has been a condition of the musealisation process. Important analytical concepts in the study are musealisation, institutionalisation, professionalisation and scientisation.
|
|
50. |
- Adloff, C, et al.
(författare)
-
Energy flow and rapidity gaps between jets in photoproduction at HERA
- 2002
-
Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 24:4, s. 517-527
-
Tidskriftsartikel (refereegranskat)abstract
- Dijet events in photon-proton collisions in which there is a large pseudorapidity separation, Deltaeta > 2.5 between the two highest E-T jets are studied with the H1 detector at HERA. The inclusive dijet cross sections are measured as functions of the longitudinal momentum fractions of the proton and photon which participate in the production of the jets, x(p)(jets) and x(gamma)(jets) respectively, Deltaeta, the pseudorapidity P separation between the two highest E-T jets, and E-T(gap), the total summed transverse energy between the jets. Rapidity gap events are defined as events in which E-T(gap) is less than E-T(cut), for E-T(cut) varied between jets 0.5 and 2.0 GeV. The fraction of dijet events with a rapidity gap is measured differentially in Deltaeta, x(p)(jets) and x(gamma)(jets). An excess of events with rapidity gaps at low values of E-T(cut) is observed above the expectation from standard photoproduction processes. This excess can be explained by the exchange of a strongly interacting colour singlet object between the jets.
|
|