| 1. |
- Grubb, Anders, et al.
(författare)
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Generation of a new cystatin C-based estimating equation for glomerular filtration rate by use of 7 assays standardized to the international calibrator
- 2014
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Ingår i: Clinical Chemistry. - : Oxford University Press (OUP). - 0009-9147 .- 1530-8561. ; 60:7, s. 974-986
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Many different cystatin C-based equations exist for estimating glomerular filtration rate. Major reasons for this are the previous lack of an international cystatin C calibrator and the nonequivalence of results from different cystatin C assays.METHODS:Use of the recently introduced certified reference material, ERM-DA471/IFCC, and further work to achieve high agreement and equivalence of 7 commercially available cystatin C assays allowed a substantial decrease of the CV of the assays, as defined by their performance in an external quality assessment for clinical laboratory investigations. By use of 2 of these assays and a population of 4690 subjects, with large subpopulations of children and Asian and Caucasian adults, with their GFR determined by either renal or plasma inulin clearance or plasma iohexol clearance, we attempted to produce a virtually assay-independent simple cystatin C-based equation for estimation of GFR.RESULTS:We developed a simple cystatin C-based equation for estimation of GFR comprising only 2 variables, cystatin C concentration and age. No terms for race and sex are required for optimal diagnostic performance. The equation, [Formula: see text] is also biologically oriented, with 1 term for the theoretical renal clearance of small molecules and 1 constant for extrarenal clearance of cystatin C.CONCLUSIONS:A virtually assay-independent simple cystatin C-based and biologically oriented equation for estimation of GFR, without terms for sex and race, was produced.
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| 2. |
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| 3. |
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| 4. |
- Bi, Zhaoxia, et al.
(författare)
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Self-assembled InN quantum dots on side facets of GaN nanowires
- 2018
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 123:16
-
Tidskriftsartikel (refereegranskat)abstract
- Self-assembled, atomic diffusion controlled growth of InN quantum dots was realized on the side facets of dislocation-free and c-oriented GaN nanowires having a hexagonal cross-section. The nanowires were synthesized by selective area metal organic vapor phase epitaxy. A 3 Å thick InN wetting layer was observed after growth, on top of which the InN quantum dots formed, indicating self-assembly in the Stranski-Krastanow growth mode. We found that the InN quantum dots can be tuned to nucleate either preferentially at the edges between GaN nanowire side facets, or directly on the side facets by tuning the adatom migration by controlling the precursor supersaturation and growth temperature. Structural characterization by transmission electron microscopy and reciprocal space mapping show that the InN quantum dots are close to be fully relaxed (residual strain below 1%) and that the c-planes of the InN quantum dots are tilted with respect to the GaN core. The strain relaxes mainly by the formation of misfit dislocations, observed with a periodicity of 3.2 nm at the InN and GaN hetero-interface. The misfit dislocations introduce I1 type stacking faults (...ABABCBC...) in the InN quantum dots. Photoluminescence investigations of the InN quantum dots show that the emissions shift to higher energy with reduced quantum dot size, which we attribute to increased quantum confinement.
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| 5. |
- Gunningberg, Per, et al.
(författare)
-
WISENET Wireless Sensor Networks VINN Excellence Center
- 2007
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- This broschure was produced for the inauguration of WISENET December 7, 2007. It decribes the future impact of WISENET, application areas and the 10 partners. The three research areas "Node Integration & Energy", "Networkning & Security" and "Wireless Communication" is briefly described as well as the application projects in "Water Sensing" and "Transport".
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| 6. |
- Razpet, A., et al.
(författare)
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Fabrication of high-density ordered nanoarrays in silicon dioxide by MeV ion track lithography
- 2005
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 97:4
-
Tidskriftsartikel (refereegranskat)abstract
- Self-assembled nanoporous alumina films were employed as masks for MeV ion track lithography. Films with thickness of 2 mum and pore diameters of 30 and 70 nm were attached to thermally grown SiO2 covered with a thin gold layer. The samples were aligned with respect to the beam by detecting backscattered He+ ions with the initial energy of 2 MeV. The ordered pattern of the porous alumina films was successfully transferred into SiO2 after irradiation with a 4 MeV Cl2+ beam at fluence of 10(14) ions/cm(2), followed by chemical etching in a 5% HF solution.
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| 7. |
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| 8. |
- Razpet, A., et al.
(författare)
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Ion transmission and characterization of ordered nanoporous alumina
- 2004
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Ingår i: Nuclear Instruments and Methods in Physics Research Section B. - : Elsevier BV. - 0168-583X .- 1872-9584. ; B:222, s. 593-600
-
Tidskriftsartikel (refereegranskat)abstract
- Ordered nanoporous alumina samples with a pore diameter of 70 nm, an array period of 100 nm and several thicknesses were considered as possible masks for pattern transfer by MeV ion lithography. A simple procedure for the sample alignment using a 2 MeV He+ beam was utilized. The energy distributions of transmitted ions as well as backscattering spectra were studied in aligned and non-aligned orientations. The best transmission, comparable to the relative surface area covered by pores, was reached for 2 mum thick samples and was independent on ion species. Although the transmission for thicker membranes was generally lower, it significantly depended on the quality of each individual sample. The presented ion beam technique can therefore be used as a tool for the characterization of porous materials. The acceptance angle for transmission through pores and the effective atomic density of samples can be obtained from the experimental data and it is shown that nanoporous alumina can be used as a mask for MeV ion lithography.
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| 9. |
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| 10. |
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| 11. |
- Andersson, Anders, 1983-, et al.
(författare)
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Co-simulation architecture with pedestrian, vehicle, and traffic simulators
- 2021
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Ingår i: Actes (IFSTTAR). - : Driving Simulation Association. ; , s. 181-184
-
Konferensbidrag (refereegranskat)abstract
- Automated and connected traffic systems with cooperative functionality need effective testing. One way to enable such testing is to represent the current traffic environment by co-simulating different simulators using a communication layer between the simulators for cooperative functionality. With this approach, this paper presents a platform with its included simulators (vehicle, pedestrian, and traffic simulators), the used run-time infrastructure (RTI) for co-simulation, and the connection to the Unreal Engine based visual system for the simulators. The architecture was tested with two vehicle simulators (one autonomous bus and a truck), one pedestrian simulator, and one traffic simulator connected using a cloud-based service for the RTI.
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| 12. |
- Andersson, Arne, et al.
(författare)
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Ottenby fågelstation : Årsrapport 1999
- 1999
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Decenniets, seklets och milleniets sista år blev ett år av stora förändringar vid Ottenby fågelstation. Deföregående tre-fyra åren hade präglats av mycket dålig ekonomi och därtill personalproblem. Under 1998blev situationen akut. Som ett första led i att förbättra situationen ombildades Ottenbykommittén (avSveriges Ornitologiska Förening satt att sköta fågelstationen) under hösten 1998. Den störstaförändringen blev sedan att Jan Pettersson, platschef sedan 1978, sades upp. Därtill kom uppsägning,pensionering, dödsfall (se nedan) och sedan tidigare överflyttade tjänster till OFAB, vilket innebar detatt den “fast” anställda personalstyrkan, som 1992 var 7 personer, reducerades till noll!Ottenbykommittén har nu fått en mycket mer aktiv roll i stationens arbete. Olika verksamhetsdelar haridentifierats och ledamöterna har getts olika ansvarsområden.Kommittén bestod under året av :Åke Lindström (ordförande)Christian Hjort (sekreterare, utlandsverksamheten)Dennis Kraft (ekonomi)Arne Andersson (datafrågor)Dennis Hasselquist (samordning av ansökningar)Anders Hedenström (forskningssamordnare)Niclas Jonzén (personal)Lars Lindell (SOF:s styrelse).Aktiviteterna inom dessa olika områden redovisas nedan och här skallbara de generella linjerna i arbetet läggas fram.Tvivelsutan förbättrades arbetsklimatet för den ideellt arbetandepersonalen på fågelstationen och glädjande nog var tillströmningen storav arbetsvilliga ungdomar. Stationen blev på många sätt öppnare, inteminst mot fågelskådarleden. Fler personer besökte stationen och pådetta sätt kan många fler känna sig delaktiga och trivas. Nackdelen äratt det rent praktiskt blir svårare att driva verksamheten med mångamänniskor närvarande och relativt stor omsättning på personer.Genom mycket hård åtstramning på utgiftssidan kunde ett förväntat rejält underskott i budgeten vändastill en liten vinst. Alla inblandade skall ha stor ära av detta eftersom både stora som små uppoffringarkrävts för att styra ekonomin rätt. Den lilla vinsten användes till att börja täcka det underskott somunder många år ackumulerats. Även om det nu känns som att vi har en god kontroll över den löpandeekonomin så måste vi på lång sikt hitta fler finansieringskällor till stationens verksamhet. Det är tillexempel mycket otillfredsställande att vi nu inte har någon heltidsanställd personal, något som på siktmåste lösas.Fågelstationens gamla dröm om att ha en egen filial söder om Sahara gick i uppfyllelse under 1999 meden månads försöksverksamhet i Nigeria under våren. Denna slog väl ut på alla sätt och verksamhetenskall nu intensifieras under 2000.Datahanteringen fick sig en rejäl skjuts framåt under året och kan vi bara snart förnya maskinparken finnsgrunden för en smidig och effektiv datahantering vid stationen. Detta kommer att underlätta bådeutåtriktad verksamhet (Internet) och eget analysarbete.Ottenby Försäljnings AB (OFAB), som drivit den affärsmässiga delen av stationens verksamhet sedan1995, fortsatte sin verksamhet parallellt med fågelstationens ideella verksamhet. Genom verksamheten iNaturum och restaurang Fågel Blå svarar OFAB för en viktig del av fågelstationens publika aktiviteter.Det är av stor vikt för framtiden att behålla och utveckla det goda samarbetet mellan fågelstationen ochOFAB.Figur 1. Åke LindströmFigur 2. Patrik Rhönnstad, platschef 1999Kontinuiteten i det praktiska arbetet på stationen blev naturligtvis något lidande av att den rutineradepersonalen försvunnit. Situationen hjälptes dock upp signifikant av att OFABs personal fanns på plats(Håkan och Annika Lundkvist, Gösta Friberg) samt att nye platschefen och många av de ideelltarbetande hade erfarenhet från tidigare år.
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| 13. |
- Bolling, Anne, et al.
(författare)
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Improving the realism in the VTI driving simulators : Shake final report
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Väg- och transportforskningsinstitutet (VTI) har tre avancerade körsimulatorer med rörelsesystem. Syftet med detta projekt var att utveckla och implementera nya modeller för grafik, vibrationer och buller, allt i syfte att öka realismen för föraren i simulatorn. Vidare skulle en valideringsstudie genomföras. Inom ramen för projektet uppnåddes följande:Utveckling av ett nytt grafiskt programpaket•Förbättring av modellerna för vibrationer på grund av däck/väg•Förbättring av rörelsesystemet genom förskjutning av rotationscentrum•Förbättring av modulen för buller, genom återskapande av däck- och vägbuller.•Synkronisering mellan vägytans grafiska presentation, buller och vibrationer .Modellernas validitet testades i VTI:s simulator III. Statistisk testning av skillnader mellan verklig bil och simulator indikerade absolut validitet för subjektiva bedömningar av vägytans jämnhet och tysthet och för det objektiva måttet hastighet, med undantag av områden där hastighetsgränsen ändrades. I dessa områden erhölls endast relativ validitet eftersom både accelerationer och retardationer var snabbare i simulatorn än i verklig bil. Relativ validitet indikerades också för det subjektiva måttet generell komfort. Resultaten från de olika valideringarna visar att förbättringarna har varit framgångsrika och föraren i simulatorn kan nu se, höra och känna ojämnheter i vägbanan exakt när hjulen träffar dessa. Fortfarande återstår dock många möjligheter till ytterligare förbättringar i simulatormodellerna.
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| 14. |
- Bolling, Anne, et al.
(författare)
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SHAKE - an approach for realistic simulation of rough roads in a moving base driving simulator
- 2010
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Ingår i: Trends in driving simulation design and experiments. - Arcueil : Institut national de recherche sur les transports et leur securite, INRETS. - 9782857826859 ; , s. 135-143
-
Konferensbidrag (refereegranskat)abstract
- With today’s advanced measurement equipment for measuring roads, it is possible to measure road geometry at high precision within a large span of wavelengths. Detailed information about the roads longitudinal and lateral profile, including macro texture, would in theory be sufficient for a realistic reproduction of road induced vibration and noise in a driving simulator. Especially, it would be possible to create a direct connection between the visual information of the road condition and the ride experience, which would increase the level of realism in the simulation. VTI has during three years performed an internal project called SHAKE with the aim to develop and implement models in VTI driving simulator III that use measured road data for generating realistic vibrations and audible road noise connected to the visual impression presented on the projection screen. This has indeed resulted in an more realistic driving experience, and a validation study with test persons driving both in the simulator and in the field has been undertaken. The OpenDRIVE standard is used as a framework for describing the road properties (e.g. visual, vibrations and noise). For this purpose some augumentations to the OpenDRIVE standard had to be made. This paper describes the technical implementations in the driving simulator, along with results from test drives on the implemented road sections
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| 15. |
- Broholm, Christa, et al.
(författare)
-
Epigenome- and Transcriptome-wide Changes in Muscle Stem Cells from Low Birth Weight Men
- 2020
-
Ingår i: Endocrine Research. - : Informa UK Limited. - 0743-5800 .- 1532-4206. ; 45:1, s. 58-71
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Being born with low birth weight (LBW) is a risk factor for muscle insulin resistance and type 2 diabetes (T2D), which may be mediated by epigenetic mechanisms programmed by the intrauterine environment. Epigenetic mechanisms exert their prime effects in developing cells. We hypothesized that muscle insulin resistance in LBW subjects may be due to early differential epigenomic and transcriptomic alterations in their immature muscle progenitor cells. Results: Muscle progenitor cells were obtained from 23 healthy young adult men born at term with LBW, and 15 BMI-matched normal birth weight (NBW) controls. The cells were subsequently cultured and differentiated into myotubes. DNA and RNA were harvested before and after differentiation for genome-wide DNA methylation and RNA expression measurements. After correcting for multiple comparisons (q ≤ 0.05), 56 CpG sites were found to be significantly, differentially methylated in myoblasts from LBW compared with NBW men, of which the top five gene-annotated CpG sites (SKI, ARMCX3, NR5A2, NEUROG, ESRRG) previously have been associated to regulation of cholesterol, fatty acid and glucose metabolism and muscle development or hypertrophy. LBW men displayed markedly decreased myotube gene expression levels of the AMPK-repressing tyrosine kinase gene FYN and the histone deacetylase gene HDAC7. Silencing of FYN and HDAC7 was associated with impaired myotube formation, which for HDAC7 reduced muscle glucose uptake. Conclusions: The data provides evidence of impaired muscle development predisposing LBW individuals to T2D is linked to and potentially caused by distinct DNA methylation and transcriptional changes including down regulation of HDAC7 and FYN in their immature myoblast stem cells.
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| 16. |
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| 17. |
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| 18. |
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| 19. |
- Cheng, Shi, et al.
(författare)
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Foldable and stretchable liquid metal planar inverted cone antenna
- 2009
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Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X .- 1558-2221. ; 57:12, s. 3765-3771
-
Tidskriftsartikel (refereegranskat)abstract
- A mechanically flexible planar inverted cone antenna (PICA) for ultrawideband (UWB) applications is presented. It can be both folded and stretched significantly without permanent damage or loss of electrical functionality. The antenna is manufactured with a process in which conductors are realized by injecting room temperature liquid metal alloy into micro-structured channels in an elastic dielectric material. The elastic dielectric material together with the liquid metal enables bending with a very small radius, twisting, and stretching along any direction. Port impedance and radiation characteristics of the non-stretched and stretched antenna are studied in simulations and experiments. The presented antenna has a return loss better than 10 dB within 3-11 GHz and a radiation efficiency of > 70% over 3-10 GHz, also when stretched. Tests verify that stretching up to 40% is possible with maintained electrical performance. The presented antenna is useful for example for body-worn antennas and in applications in harsh environments where mechanical flexibility helps improve durability.
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| 20. |
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| 21. |
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| 22. |
- Cheng, Shi, et al.
(författare)
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Liquid metal stretchable unbalanced loop antenna
- 2009
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 94:14, s. 144103-
-
Tidskriftsartikel (refereegranskat)abstract
- We present a 2.4 GHz unbalanced loop antenna that can be stretched along multiple dimensions simultaneously. It was realized by incorporating room temperature liquid metal alloy into microstructured channels in an elastic material. The demonstrated prototype exhibits a stretchability of up to 40% along two orthogonal orientations as well as foldability and twistability. Port impedance and radiation characteristics of the nonstretched and stretched antenna were studied numerically and experimentally. Measured results indicate a radiation efficiency of more than 80%.
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| 23. |
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| 24. |
- Chu, Jiangtao, et al.
(författare)
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Impact of static pressure on transmembrane fluid exchange in high molecular weight cut off microdialysis
- 2014
-
Ingår i: Biomedical microdevices (Print). - : Springer Science and Business Media LLC. - 1387-2176 .- 1572-8781. ; 16:2, s. 301-310
-
Tidskriftsartikel (refereegranskat)abstract
- With the interest of studying larger biomolecules by microdialysis (MD), this sampling technique has reached into the ultrafiltration region of fluid exchange, where fluid recovery (FR) has a strong dependence on pressure. Hence in this study, we focus on the fluid exchange across the high molecular weight cut off MD membrane under the influence of the static pressure in the sampling environment. A theoretical model is presented for MD with such membranes, where FR has a linear dependence upon the static pressure of the sample. Transmembrane (TM) osmotic pressure difference and MD perfusion rate decide how fast FR increases with increased static pressure.A test chamber for in vitro MD under static pressure was constructed and validated. It can hold four MD probes under controlled pressurized conditions. Comparison showed good agreement between experiment and theory. Moreover, test results showed that the fluid recovery of the test chamber MD can be set accurately via the chamber pressure, which is controlled by sample injection into the chamber at precise rate. This in vitro system is designed for modelling in vivo MD in cerebrospinal fluid and studies with biological samples in this system may be good models for in vivo MD.
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| 25. |
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| 26. |
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| 27. |
- Dahl, Gudrun, et al.
(författare)
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Precolonial Beja : A periphery at the crossroads
- 2006
-
Ingår i: Nordic Journal of African Studies (NJAS). - Finland. - 1459-9465. ; 15:4, s. 473-498
-
Tidskriftsartikel (refereegranskat)abstract
- The Beja, or Bedawiye, people speaking the Northern Cushitic language called “Bedawiet”, have literally since “time immemorial” occupied the Eastern deserts of Sudan, Egypt and possibly Eritrea. They today consist of the subgroups Ababda, Bishariin, Atmaan/Amar´ar, Hadendowa and sections of the Beni Amer. These subgroups are relatively loosely integrated confederations of endogamous lineages based on assumptions of shared descent and cohabitation in an ancestral territory. In this hot and arid land, where there is little evidence of large-scale climatic change the last 2500 years, they have eked out a livelihood presumably originally as hunters of wild game and gatherers of wild grain, later as herders of small stock in the drier areas and of cattle in the delta lands, combining pastoralism with some take-a-chance cultivation. Some centuries after Christ they also acquired camels and became mounted brigands, guides and sycesin relation to the caravan trade. The present paper is an attempt to trace what can be said about the way larger context of empires, trade routes and security impinged on their lives in pre-colonial times.
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| 28. |
- Dahlin, Andreas P., et al.
(författare)
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Methodological aspects on microdialysis protein sampling and quantification in biological fluids : an in vitro study on human ventricular CSF.
- 2010
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Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 0003-2700 .- 1520-6882. ; 82:11, s. 4376-4385
-
Tidskriftsartikel (refereegranskat)abstract
- There is growing interest in sampling of protein biomarkers from the interstitial compartment of the brain and other organs using high molecular cutoff membrane microdialysis (MD) catheters. However, recent data suggest that protein sampling across such MD membranes is a highly complex process that needs to be further studied. Here, we report three major improvements for microdialysis sampling of proteins in complex biological matrixes. The improvements in this in vitro study using human ventricular cerebrospinal fluid as the sample matrix include increased fluid recovery control, decreased protein adsorption on the microdialysis membrane and materials, and novel quantitative mass spectrometry analysis. Dextrans in different concentrations and sizes were added to the perfusion fluid. It was found that dextrans with molecular mass 250 and 500 kDa provided a fluid recovery close to 100%. An improved fluid recovery precision could be obtained by self-assembly triblock polymer surface modification of the MD catheters. The modified catheters also delivered a significantly increased extraction efficiency for some of the investigated proteins. The final improvement was to analyze the dialysates with isobaric tagged (iTRAQ) proteomics, followed by tandem mass spectrometric analysis. By using this technique, 48 proteins could be quantified and analyzed with respect to their extraction efficiencies. The novel aspects of microdialysis protein sampling, detection, and quantification in biological fluids presented in this study should be considered as a first step toward better understanding and handling of the challenges associated with microdialysis sampling of proteins. The next step is to optimize the developed methodology in vivo.
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| 29. |
- Dahlman, Joakim, et al.
(författare)
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Realtidskartor i kollektivtrafiken : What you see is where you get
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Inom ramen för projektet What you see is where you get har upplevda och faktiska nyttor med en så kallad realtidskarta för kollektivtrafik studerats. Projektet undersöker om en realtidskarta kan förenkla och förändra resenärers beslutsfattande vid kollektivt resande. Vi vill ta reda på resenärers informationsbehov, beslut och önskemål med ett sådant verktyg. På senare tid har en mängd tekniska tjänster som förser kollektiv-trafikresenärer med uppgifter om fordons tillgänglighet i form av tid och plats introducerats. Antagandet för projektet är att tillgången till en bra karta i realtid med olika funktioner skulle kunna förändra och eventuellt förenkla resandet. För att besvara frågorna knutna till detta har attityder, önskemål, behov och användning testats hos såväl kollektiv-trafikresenärer som operatörer/kollektivtrafikmyndigheter.Då realtidskartan visades för tre grupper av resenärer i olika åldrar visade resultaten att samtliga var positiva och kunde tänka sig att använda realtidskartan, som ett komplement till den reseplaneringsapplikation de redan använde. Realtidskartan behövde utvecklas för att bli mer hanterbar och kunna fylla fler behov.Då realtidskartan visades på en busshållplats där resenärerna på en skärm kunde se de vanliga tidsangivelserna växelvis med en realtidskarta, visade resultaten ett lågt intresse för kartan. En introduktion eller instruktion skulle behövas. Ett antal resenärer testade realtidskartan under en resa i staden. I projektet intervjuades även resenärer vid hållplatser om de uppmärksammat och använde realtidskartan i reseplaneringsappen.En övergripande slutsats är att man även inom kollektivtrafikbranschen verkar ha svårt att (mer teoretiskt) sätta sig in i det nya koncept som realtidskartor innebär, och att det ännu är få som har använt dem när de reser. En ytterligare slutsats, från jämförelse mellan de individuella enkätsvaren, är att de som faktiskt hade använt realtidskartor när de reser också hade attityder som reflekterade att de både kunde vara mycket nöjda och mycket missnöjda med hur realtidskartan fungerat.
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| 30. |
- Dancila, Dragos, et al.
(författare)
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A compact 10 kW solid-state RF power amplifier at 352 MHz
- 2017
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Ingår i: Journal of Physics, Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 874
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Tidskriftsartikel (refereegranskat)abstract
- A compact 10 kW RF power amplifier at 352 MHz was developed at FREIA for the European Spallation Source, ESS. The specifications of ESS for the conception of amplifiers are related to its pulsed operation: 3.5 ms pulse length and a duty cycle of 5%. The realized amplifier is composed of eight kilowatt level modules, combined using a planar Gysel 8-way combiner. The combiner has a low insertion loss of only 0.2 dB, measured at 10 kW peak power. Each module is built around a commercially available LDMOS transistor in a single-ended architecture. During the final tests, a total output peak power of 10.5 kW was measured.
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| 31. |
-
Ecology and politics : environmental stress and security in Africa
- 1989
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Proceedings (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- Environmental issues are all too often treated separately from politics and social change. This volume tries to redress the balance. Common to the essays is a search for the interrelationship between ecological stress and politics.
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| 32. |
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| 33. |
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| 34. |
- Ettema, Thijs J. G., et al.
(författare)
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Rolf Bernander (1956-2014) : pioneer of the archaeal cell cycle Obituary
- 2014
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Ingår i: Molecular Microbiology. - : John Wiley & Sons. - 0950-382X .- 1365-2958. ; 92:5, s. 903-909
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- On 19 January 2014 Rolf (Roffe') Bernander passed away unexpectedly. Rolf was a dedicated scientist; his research aimed at unravelling the cell biology of the archaeal domain of life, especially cell cycle-related questions, but he also made important contributions in other areas of microbiology. Rolf had a professor position in the Molecular Evolution programme at Uppsala University, Sweden for about 8 years, and in January 2013 he became chair professor at the Department of Molecular Biosciences, The Wenner-Gren Institute at Stockholm University in Sweden. Rolf was an exceptional colleague and will be deeply missed by his family and friends, and the colleagues and co-workers that he leaves behind in the scientific community. He will be remembered for his endless enthusiasm for science, his analytical mind, and his quirky sense of humour.
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| 35. |
- Fagerström, Anton, et al.
(författare)
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Large scale bio electro jet fuel production integration at CHP-plant in Östersund, Sweden
- 2021. - B 2407
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This document reports the findings of the project “Large scale bio electro jet fuel production integration at CHP-plant in Östersund, Sweden”. BEJF is an electrofuel produced in a synthesis process where biogenic carbon dioxide (CO2) is the main carbon source and hydrogen from electrolysis of water using renewable electricity is the main energy source. The project is a feasibility study for a factory for such fuel located at Jämtkraft's facility for CHP in Östersund. Thus, the aim of the project is to assess the feasibility for producing renewable aviation fuel at a specific location considering and evaluating e.g., different processes, operations and integrations, costs, environmental impact, business models and actors.IVL The Swedish Environmental Research Institute, Jämtkraft (JK), Chalmers University (CU), Lund University (LU), Nordic Initiative for Sustainable Aviation (NISA), and Fly Green Fund (FGF) have been the primary implementers in this project. Other project stakeholders (AFAB, and The Power Region), have provided relevant data to the various working groups. The project has included experimental work, modelling and calculations, as well as literature-based studies but not the construction of any facilities.
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| 36. |
- Grahn, Desirée, et al.
(författare)
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Förnybar flytande biogas (LBG) till sjöfart i praktiken
- 2024
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Reducing the environmental and climate impact of shipping propelled by liquefied natural gas (LNG) requires the introduction of alternative fuels such as liquid biogas/biomethane (LBG) (Jivén et al., 2022). Today, only a small part of the biomethane produced in Sweden is liquefied into LBG and an even smaller part is used as fuel for shipping. The price and availability of biogas is governed by supply and demand in an international market where shipping, industry and heavy trucks demand biogas. The biogas then needs to be processed into upgraded biogas (biomethane) or LBG quality in order to be transported and used in the respective sectors inside and outside of Sweden. The trend is for a larger proportion of biogas to be liquefied into LBG. The market has thus gone from a local market, where biogas was produced in the city's wastewater treatment plant and the city buses ran on biogas, to an international market where biogas often is transported in the same way as fossil gas and marketed using the fossil gas together with certificates. The project "Renewable liquid biogas (LBG) for shipping in practice" was carried out by IVL Swedish Environmental Research Institute and RISE in 2023 together with stakeholders from the shipping sector, ports and industry organizations for biogas. The project has studied the conditions required to make LBG available to shipping in practice at Swedish ports. The study shows that the major obstacles to an established use of LBG in the shipping sector in Sweden today are pricing/willingness to pay that is affected by international market prices, lack of suitable logistical solutions as well as the absence of the piece of the puzzle that is the business model and cooperation needed to make available the large volumes of biogas that shipping may demand. The stakeholders in the project estimate their total need of biogas to 3 TWh in a short term, and 10 TWh in a longer term. The project has identified a number of conclusions and recommendations for future work, including that the potential for biogas is large and untapped, but that new solutions for the distribution and logistics of LBG are needed. There is a clear interest from maritime actors as they see biogas as a strategic solution and the dialog between actors in the industry remains important. A change in the tax system could be needed so that more actors can use the green gas principle for LBG. In addition, a functioning "marketplace" is needed, which simplifies for sellers and buyers of LBG, and agreements/contracts are needed that are longterm and to a greater extent based on the costs of producing and providing LBG.
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| 37. |
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| 38. |
- Gustafsson, Mats, et al.
(författare)
-
Effekter av vinterdäck : en kunskapsöversikt
- 2006
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Choice of winter tyres has, from mainly being a matter of safety and economic costs for wearing of road pavements, during later years also become a matter of inhalable particles formed during pavement wear from studded tyres and their negative effects on public health. Further, the tyres' effects on environment and noise have been illustrated in several studies. The issue is also complicated by the fact that tyre choice effects on traffic safety have several components, including such diverging parameters as friction and behaviour. Finally all aspects have to be evaluated from a socioeconomic point of view for society to be able to decide which kind of distribution of tyre types that is the most profitable. This report is a summary of current knowledge in this complex research field.
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| 39. |
- Gustafsson, Mats, et al.
(författare)
-
NanoWear : nanopartiklar från slitage av däck och vägbana
- 2009
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Particles from road and tire wear have in recent years come to the fore as an important and relatively unexplored contribution to air particulate pollution. Mechanically generated wear particles are relatively coarse (>0.5 microns), but in controlled trials in VTI's road simulator it has been found that an ultra-fine fraction (< 100 nm) of particles is formed from tyre and pavement wear. This project was initiated to identify the source of these nanoparticles. The results show that the nanoparticles of the size 30-50 nm occur only from tests with studded tyres. One of the two tested Nordic unstudded winter tyres produced an even finer particle fraction (<10 nm), while the other unstudded winter tyre type did not give rise to nanoparticles. Tests with summer tyres did not result in the formation of nanoparticles. It is clear that the fine particle fraction contains higher relative concentrations of sulphur, which is present at relatively high levels in both bitumen and tyres. It is unclear whether the ultrafine particles formed from studded tyre wear of road pavement in the road simulator also occur in real traffic. If so, this may affect the assessment of health effects from different traffic related particle sources.
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| 40. |
- Gustavsson Binder, Tobias, et al.
(författare)
-
Bränslecellsbussar i kallt klimat : ett utsläppsfritt alternativ till batteribussar?
- 2024
-
Ingår i: Sammanställning av referat från Transportforum 2024. - Linköping : Statens väg- och transportforskningsinstitut. ; , s. 352-353
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Kollektivtrafiken har länge varit en föregångare i att minska klimatutsläpp. Framför allt stadsbusstrafik kommer att ta snabba steg mot nollemissionsdrift framöver. Vid sidan av batterielektriska bussar riktas alltmer fokus mot bränslecellsbussar som drivs med vätgas. I flera städer i Europa görs satsningar på vätgas i kollektivtrafiken och flera stora busstillverkare släpper sådana modeller. Bränslecellsbussar har både för- och nackdelar gentemot batteribussar. En möjlig fördel i kallt klimat är att vätgasbussen kan nyttja spillvärme från bränslecellen för uppvärmning och därmed inte vara beroende av en tilläggsvärmare som förbränner diesel. En möjlig nackdel är att bränslecellsbuss kan vara dyrare i inköp och vid drift. Det här projektet syftar till att utreda möjligheterna att producera vätgas från biogas som produceras från avloppsslam för att använda sig av vätgasen i bränslecellsbussar i stadstrafik i kallt klimat. Bakgrunden är att många biogasproducenter, bland annat i Luleå, söker nya användningsområden för biogas då användningen i stadsbussar sannolikt kommer minska närmaste decennium. Projektet utgår från ett systemperspektiv där användningen av vätgas i bränslecellsbuss jämförs med batteribussar ur ett ”Well-to-Wheel”-perspektiv med avseende på energieffektivitet, teknikmognad, investerings- och driftkostnader samt klimatnytta. ”Total Cost of Ownership” beräknas även för bränslecellsbussar och jämförs med batteribussar. Fyra olika möjliga lösningar för lokal produktion av vätgas i Luleå jämförs ur ett ”Well-to-Tank”-perspektiv. De fyra lösningar som utvärderas är: Produktion av vätgas genom elektrolys av vattenProduktion av vätgas genom reformering av uppgraderad biogasProduktion av vätgas genom reformering av rå biogasProduktion av vätgas genom pyrolys av uppgraderad biogasVätgasen producerad via de fyra olika lösningarna transporteras sedan på samma sätt till tankstation för bussar med gasflak på lastbil för snabbtankning vid bussdepå. Användningen av vätgas i bränslecellsbuss jämförs sedan med batteribuss ur ett ”Tank-to-Wheel”-perspektiv.Preliminära resultat indikerar att kostnaden för vätgas till stor del är beroende av elpriset och priset på rå biogas respektive uppgraderad biogas samt inköpspriset för vissa delsystem.
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| 41. |
- Gustavsson Binder, Tobias, et al.
(författare)
-
Hydrogen from biogas as fuel for buses in cold climate - Analysing the feasibility to produce hydrogen from local biogas and use in city buses in Luleå
- 2024
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In this study, we demonstrate that in certain cases, it can be advantageous to produce hydrogen from biogas and to use it in heavy-duty vehicles such as buses. In Luleå, it may be feasible to use hydrogen from biogas in city buses because there is a need for heating where waste heat from the fuel cell can be utilized. However, it is uncertain whether the waste heat is sufficient or if a separate auxiliary heater driven by diesel or HVO is needed. If such a heater is required, the conclusion is that hydrogen from biogas is suitable for other segments of heavy transportation, where battery electrification is not as suitable. Overall, our study shows that hydrogen from biogas may be interesting as a transitional fuel to increase the availability of environmentally friendly hydrogen until electrolyzer capacity is sufficiently expanded.At the same time, our mapping of the policy landscape concerning hydrogen and zero-emission buses shows that biohydrogen is disadvantaged in the EU's regulations on renewable hydrogen. This means that member states are restricted from providing support for investments to produce and distribute hydrogen from biogas and other biogenic feedstocks. The reason is that renewable hydrogen, according to EU terminology, is defined in the so-called delegated act on renewable fuels of non-biological origin (RFNBO). It is established that renewable hydrogen should be based on non-biological feedstocks (i.e., from electrolysis) and must meet a number of criteria.The results are interesting in the context of urban bus traffic rapidly moving towards zero-emission operation. In Sweden and many other countries, battery buses have become a common and obvious feature on city streets. But just like for other segments of heavy-duty vehicles, another technology to achieve zero-emission operation has also received increased attention, namely hydrogen and fuel cell buses. In Sweden, only a few fuel cell buses have been used - and moreover, only on a trial basis - but in several European cities, they have already begun to be used on a significant scale. An advantage of fuel cell operation with hydrogen from biogas is that it allows for the continued utilization of the biogas already produced and purchased for existing city bus traffic.System study consisting of two partsWe arrived at the result by investigating the suitability of both producing hydrogen from biogas at the existing sewage treatment plant in Luleå and the feasibility for LLT to use fuel cell buses in its city bus traffic. The study has considered both costs associated with each part and climate impact from a life cycle perspective for fuel production and bus operation.
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| 42. |
- Hajdu, Flora, 1976-
(författare)
-
Local Worlds : Rural Livelihood Strategies in Eastern Cape, South Africa
- 2006
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Local perceptions and livelihood strategies have in this study been examined through extensive fieldwork in two villages in rural Pondoland in the former homeland Transkei in South Africa’s Eastern Cape Province. Using a bottom-up perspective, changes in livelihoods and the processes involved in choosing between and combining various types of livelihood activities are analysed. The study also looks at specific South African policies, targeted at poverty relief and restriction of natural resource use, from the local perspective and points at communication problems between the national and local levels.Livelihoods in Transkei are today often conceptualised as consisting of subsistence agriculture combined with monetary incomes in the forms of state pensions and remittances from migrant labourers. This view is challenged by the results of the present study, showing that local jobs are the major components of livelihoods in the studied villages. Informal jobs are stressed as constituting an important, and perhaps previously underestimated, part of local job opportunities. While pensions also do make important contributions to livelihoods, the significance of agriculture, livestock keeping and various forms of natural resource use is shown to be relatively low. Key insights are that livelihood activities in rural Transkei vary a lot between specific localities, and that important recent changes in livelihoods have taken place.Transkei is furthermore often conceptualised as a region where severe environmental degradation is taking place, a fact that is also contradicted by findings from the study area. In accordance with recent research on an ‘African degradation narrative’, the hopeless and homogenous picture of Transkei as a generally degraded region is questioned. These results are also used to critically examine concepts such as ‘multiple livelihood strategies’ and the tendency to generalise about rural livelihoods across regions, countries or even continents.
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| 43. |
- Hallberg, Elisabet, et al.
(författare)
-
Miljöbedömning av matavfallsemballage - Livscykelanalys av olika påsalternativ
- 2018
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Matavfall används ofta i Sverige för att producera biogödsel och biogas. Olika typer av matavfallsemballage (matavfallspåsar) kan användas för insamling av matavfall, t ex: plastpåsar av polyeten (fossil- eller bio-baserade), påsar från material baserade på majs- eller potatisstärkelse, papperspåsar. Alternativen har olika egenskaper och olika fördelar och nackdelar. Många kommuner i Sverige ställer krav på en specifik typ av emballage som ska användas. Idag finns det inga speciella krav för matavfallsemballage för insamling av matavfall i Uppsala kommun och hushållen väljer själva vilken typ av påse som används. Uppsala Vatten vill undersöka om det ur hållbarhetssynpunkt finns skäl att göra förändringar av dagens insamlingssystem. I den här studien gjordes en miljöutvärdering av olika typer av matavfallsemballage för insamling från hushåll. Projektets syfte var att adressera frågeställningen hur matavfallsemballage av olika material påverkar klimatprestandan för insamling och rötning av matavfall. Studien har, genom livscykelanalys (LCA), utforskat, utvärderat och dokumenterat klimatpåverkan från olika matavfallsemballage längs hela värdekedjan. Olika fördelar och nackdelar av materialval samt distribution av matavfallspåsar har också identifierats med hjälp av intervjuer med olika kommuner och företag i Sverige. De olika typerna av påsar för matavfallsemballage som har analyserats i den här studien är: fossil polyeten (PE), (bärkasse och avfallspåse på rulle); återvunnen PE (bärkasse och avfallspåse på rulle), bio-baserad PE (bärkasse och avfallspåse på rulle) samt kompostpåse (papper). En viktig del av en LCA-beräkning är att sätta systemgränser för vilka delar av livscykeln som beräkningen ska täcka in. Detta beror i sin tur på hur produkten används. I denna studie har t. ex. inte tillverkningen av råvara och påse tagits med i beräkningen för plastbärkassar p.g.a. att de främst är tillverkade för att användas till ett annat ändamål. För avfallspåse på rulle och kompostpåse av papper inkluderas däremot denna tillverkning eftersom dessa påsar enbart är avsedda att användas som matavfallsemballage. Resultaten visar att bärkassen av bio-baserad PE faller bäst ut ur klimatsynpunkt eftersom utsläppet av koldioxid (CO2) vid förbränning av bio-baserad PE är biogent och därmed enligt praxis inte räknas som ett bidrag till antropogen klimatpåverkan och dessutom exkluderas tillverkningen av råvara och påse. Det bör dock påpekas att valet av en bio-baserad PE bärkasse sällan är ett val man som konsument själv kan styra över eftersom tillgången regleras av butikernas val av material i påsar. Om man enbart jämför påsar som produceras för ändamålet att samla in matavfall (där ”uppströms produktion” inkluderas) är papperspåse (kompostpåse) bästa alternativet, och avfallspåse på rulle av fossil PE faller ut sämst ur klimatsynpunkt. Att kompostpåse av papper är det mest gynnsamma alternativet, beror främst på att utsläppet av koldioxid (CO2) vid förbränning av papper är biogent (analogt med fallet för bio-baserad PE). Påverkan från tillverkningen av råvaran (papper) samt påstillverkningen är också lägre för papperspåsen. Under studien observerades dock att resultaten är mycket känsliga för vissa osäkra parametrar, t ex: antagande om volym av matavfall per påse, mängder av producerad biogödsel och biogas samt biogödselkvalitet. Känslighetsanalyser visade att dessa parametrar kan påverka jämförelsen mellan påsarna och behöver därmed studeras mer för att säkerställa pålitliga resultat.
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| 44. |
- Hansson, Anna, 1984-, et al.
(författare)
-
Biogas production in the industrial symbiosis context – facilitating collaboration through digitalization
- 2024
-
Ingår i: 5THCESUST2024: 5TH SYMPOSIUM ON CIRCULAR ECONOMY AND SUSTAINABILITY.
-
Konferensbidrag (refereegranskat)abstract
- Improving sustainability performance and adapting to circular economy principles in operational business strategies are becoming increasingly prioritized. In this pursuit, the concept of industrial symbiosis (IS) has become increasingly relevant. IS represents a collaborative approach where the interplay of material, residual waste, energy, and infrastructure exchanges aims to yield not only economic and environmental advantages for the participating companies but also substantial societal benefits by using resources more efficiently. Biogas production is such an example, it can reduce greenhouse gas emissions since it can produce heat and electricity, replace renewable fuel for vehicles, or be used as input material for industrial use. The digestate from biogas production can also be used as an effective agricultural fertilizer to replace chemical fertilizers which are produced using fossil energy.Digital tools and platforms in IS can be used to different extent depending on businesses levels of digital maturity (the extent to which businesses adapt to ongoing digital change and integrate digitalization). Digital tools and platforms hold a central role for developing various advantages in biogas-based IS, but since the digital maturity for IS focusing on biogas production is uncertain, the current efficiency obtained by tools and platforms is unknown. Therefore, through semi-structured interviews and study visits, this study assesses stakeholder collaboration and use of digital tools at five IS sites with biogas production in Sweden. It explores (i) current digital maturity and collaboration characteristics amongst established biogas-based IS, and (ii) needs amongst stakeholders for development of digital tools and platforms to promote digital maturity, monitoring, collaboration, and knowledge exchange in current and future IS structures.Preliminary results of the on-going study show that the use of digital tools varies depending on the character and size of resource flows that are included in the collaboration, and due to the internal digital maturity of the involved companies. In general, the use of digital tools for stakeholder interaction is on low or medium level, in which manual handling is required and little is automated. This complies with the sites being relatively small, and the number of stakeholders involved are relatively few. Moreover, the preliminary results show that the interest of future development of digital tools is found to be related to business development and expanded market opportunities through diversified raw material use, increased production, and new distribution channels. In addition, a demand of digital platforms for exchange of experience and competence supply has been identified.
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| 45. |
- Hestad, Monika, et al.
(författare)
-
Craft Brewery Brands: self-awareness through performance
- 2014
-
Ingår i: Erik Bohemia, Alison Rieple, Jeanne Liedtka, & Rachel Cooper (Eds.), Design Management in an Era of Disruption- Proceedings of the 19th DMI: Academic Design. - 9780615991528 ; , s. 504-529
-
Konferensbidrag (refereegranskat)abstract
- New principles emerge, with brands, innovation and design being driven bypassion and meaning. Companies strive to resonate with consumers, tappinginto culture, myths and ideologies, but also move to becoming “citizenartists” who inspire people. Design may play a central role in this,materialising values and interpreting meaning. A product category that isseemingly localised, socially engaged, and value-oriented is craft breweries.These are often small-scale and use traditional approaches to brewing,emphasising craftsmanship and quality, based on an often rebellious butplayful nature, challenging the status quo, while having a passion to learn.We aim to understand how to develop brands based on own passion andprinciples, while being open to influences in society. What is the role of designwhen establishing a craft beer brand? We conducted a comparative casestudy using interviews, site visits and extensive desktop research. The resultsare compared through a framework seeing identity as a self-image that isembodied, performed, interacted and re-negotiated in an ongoing process.Both cases actively use design and engage with their audiences, but do sowith different agendas: preserving and perfecting traditions, or playfullycreating new brews and scenes.
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| 46. |
- Hillered, Lars, et al.
(författare)
-
Cerebral microdialysis for protein biomarker monitoring in the neurointensive care setting - a technical approach
- 2014
-
Ingår i: Frontiers in Neurology. - : Frontiers Media SA. - 1664-2295. ; 5, s. 245-
-
Tidskriftsartikel (refereegranskat)abstract
- Cerebral microdialysis (MD) was introduced as a neurochemical monitoring method in the early 1990s and is currently widely used for the sampling of low molecular weight molecules, signaling energy crisis, and cellular distress in the neurointensive care (NIC) setting. There is a growing interest in MD for harvesting of intracerebral protein biomarkers of secondary injury mechanisms in acute traumatic and neurovascular brain injury in the NIC community. The initial enthusiasm over the opportunity to sample protein biomarkers with high molecular weight cut-off MD catheters has dampened somewhat with the emerging realization of inherent methodological problems including protein-protein interaction, protein adhesion, and biofouling, causing an unstable in vivo performance (i.e., fluid recovery and extraction efficiency) of the MD catheter. This review will focus on the results of a multidisciplinary collaborative effort, within the Uppsala Berzelii Centre for Neurodiagnostics during the past several years, to study the features of the complex process of high molecular weight cut-off MD for protein biomarkers. This research has led to new methodology showing robust in vivo performance with optimized fluid recovery and improved extraction efficiency, allowing for more accurate biomarker monitoring. In combination with evolving analytical methodology allowing for multiplex biomarker analysis in ultra-small MD samples, a new opportunity opens up for high-resolution temporal mapping of secondary injury cascades, such as neuroinflammation and other cell injury reactions directly in the injured human brain. Such data may provide an important basis for improved characterization of complex injuries, e.g., traumatic and neurovascular brain injury, and help in defining targets and treatment windows for neuroprotective drug development.
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| 47. |
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| 48. |
- Hjort, Anders
(författare)
-
Potentialen för biogas och bio-SNG i Sverige
- 2019
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Inom ramen för det pågående projektet Västsvensk arena för flytande biogas ansvarar IVL för systemanalyser av hållbarhetsaspekter kring produktion och användning av LBG (Liquified Bio Gas). LBG ses som ett lovande bränsle för att bidra till målet om en en fossilfri fordonsflotta. En fråga som varit viktig att besvara är hur stor potentialen för produktion av LBG är i Sverige inom de närmsta åren. Denna studie har sammanställt kunskapsläget i Sverige, konstaterat att det finns få studier som specifikt fokuserar på LBG och därför uppskattat potentialen för produktion av biogas från hållbara substrat baserat befintliga studier.
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| 49. |
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| 50. |
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