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1.	Ahrné, Karin, et al. (författare) Tillstånd och trender för arter och deras livsmiljöer – rödlistade arter i Sverige 2015 2015 Rapport (övrigt vetenskapligt/konstnärligt)abstract 2015 års upplaga av den svenska rödlistan är den fjärde i ordningen. Den är baserad på IUCN:s rödlistningskriterier och revideras vart femte år. I rödlistan bedöms risken som enskilda arter av djur, växter och svampar löper att försvinna från Sverige. Bedömningen utförs av ArtDatabankens medarbetare i samverkan med över 100 externa experter, indelade i 14 expertkommittéer för olika organismgrupper. Under arbetet med 2015 års rödlista har tillstånd och trender bedömts för 21 600 arter och 1 318 lägre taxa (apomiktiska arter, underarter och varieteter), sammanlagt ca 22 900 taxa. Av de bedömda arterna klassificerades 2 029 som hotade (kategorierna CR, EN och VU) och 4 273 som rödlistade (inkluderar även kategorierna NT, RE och DD). Förhållandet mellan antalet rödlistade och antalet bedömda arter ar 19,8 %, vilket är ungefär samma värde som 2010 och 2005. I denna rapport jämförs antalet och andelen rödlistade arter mellan olika organismgrupper, biotoper, substrat och påverkansfaktorer. Texten ar indelad i en allmän del och åtta kapitel inriktade på olika landskapstyper. Landskapstyperna utgör en grov indelning av landets miljöer enligt följande kategorier: Skog, Jordbrukslandskap, Urbana miljöer, Fjäll, Våtmarker, Sötvatten, Havsstränder och Havsmiljöer. Skogen och jordbrukslandskapet är de artrikaste landskapstyperna med 1 800 respektive 1 400 arter som har en stark anknytning dit, och ytterligare flera hundra arter som förekommer där mer sporadiskt. De faktorer som påverkar flest rödlistade arter i Sverige är skogsavverkning och igenväxning, som båda utgör ett hot mot vardera ca 30 % av de rödlistade arterna. Avverkning minskar arealen av skog där naturliga strukturer och naturlig dynamik upprätthålls, och den orsakar därmed förlust av livsmiljöer. Igenväxning orsakas av ett antal faktorer, bland annat upphörande hävd (bete och slåtter), gödsling, trädplantering och brist på naturliga störningsregimer som t.ex. regelbundna översvämningar kring vattendrag och sjöar. Andra viktiga påverkansfaktorer är fiske, torrläggning av våtmarker, tillbakagång hos värdarter (främst alm och ask som drabbats av invasiva svampsjukdomar), klimatförändringar och konkurrens från invasiva arter. IUCN:s rödlisteindex beräknas för ett urval av de bedömda organismgrupperna. Rödlisteindex visar att skillnaderna mellan rödlistorna från 2000, 2005, 2010 och 2015 är små. Ett par undantag finns dock. Groddjur och stora däggdjur har fått en något förbättrad situation sedan 2000. Totalt förefaller det ändå som att trycket mot Sveriges artstock har förblivit relativt konstant under de senaste 15 åren.
2.	Abrahamsson, Johanna, 1990, et al. (författare) A Raman spectroscopic approach to investigate the production of biodiesel from soybean oil using 1-alkyl-3-methylimidazolium ionic liquids with intermediate chain length 2015 Ingår i: Applied Energy. - : Elsevier BV. - 1872-9118 .- 0306-2619. ; 154, s. 763-770 Tidskriftsartikel (refereegranskat)abstract We present a Raman spectroscopic study of the conversion of soybean oil into biodiesel by methanol using the lipase B enzyme pseudomonas cepacia as the bio-catalyst and 1-alkyl-3-methylimidazolium ionic liquids (CnC1Im) as co-solvents, where the alkyl chain length is varied from ethyl (n=2) to decyl (n=10). We have limited this study to a low reaction temperature, 40°C, and a low enzyme concentration to investigate the possibility of producing biodiesel with low energy and cost demands. We also demonstrate that Raman spectroscopy is a powerful and straightforward method to estimate the yield of the transesterification reaction, by analysis of the characteristic CO stretching mode found in the range ~1730-1750cm-1. Our results indicate that both reaction yield and reaction rate increase with the chain length, but also that for chains longer than decyl further improvements are marginal. We discuss these results from the viewpoint of local interactions and local structure of the investigated ionic liquids.
3.	Aronsson, Mora, et al. (författare) Sveriges arter och naturtyper i EU:s art- och habitatdirektiv : Resultat från rapportering 2019 till EU av bevarandestatus 2013-2018 2020 Rapport (övrigt vetenskapligt/konstnärligt)abstract Sverige har en variationsrik natur med storslagen fjällmiljö, myllrande våtmarker, vattendrag och sjöar, kust och hav, skogar och odlingslandskap, alla med ett rikt växt och djurliv. Den här fantastiska biologiska mångfalden tas ofta för given och ibland som en lyx, men oavsett vilket är det en förutsättning för vår överlevnad.2019 rapporterade Sverige statusen till EU för perioden 2013–2018 för de naturtyper och arter i Sverige som är listade i art- och habitatdirektivet. Den berättar att 20 procent av naturtyperna och 40 procent av arterna mår bra. Den biologiska mångfalden är hårt trängd i såväl Sverige som i andra EU-länder.Den här rapporten sammanfattar Sveriges rapportering och innehåller beskrivningar av status för naturtyper och arter, påverkan, hot och trender. Rapporten ger kunskap om tillståndet för den biologiska mångfalden i Sverige med hjälp av de arter och naturtyper som är listade i EU:s art- och habitatdirektiv.Rapporten visar hur naturmiljöerna i Sverige förändas, och sammanfattar den senaste kunskapen om vilka faktorer som driver dessa förändringar. Även exempel på hur vi genom restaurerings- och skötselåtgärder kan hejda förlusten av biologisk mångfald tas upp.
4.	Bergman, Torbjörn, 1957-, et al. (författare) Det finns möjligheter till blocköverskridande samarbeten 2015 Annan publikation (populärvet., debatt m.m.)
5.	Bergman, Torbjörn, 1957-, et al. (författare) DÖ är inte hållbar i längden 2015 Annan publikation (populärvet., debatt m.m.)
6.	Bergvall, Niklas, et al. (författare) Continuous Slurry Hydrocracking of Biobased Fast Pyrolysis Oil 2021 Ingår i: Energy & Fuels. - : American Chemical Society. - 0887-0624 .- 1520-5029. ; 35:3, s. 2303-2312 Tidskriftsartikel (refereegranskat)abstract Co-refining of fast pyrolysis bio-oil together with fossil oil in existing refinery infrastructure is an attractive and cost-efficient route to conversion of lignocellulosic biomass to transportation fuel. However, due to large differences in properties between the two oils, special notice is needed to reduce process-related issues. Here, fast pyrolysis bio-oil produced from lignocellulosic biomass was co-refined with vacuum gas oil at a 20:80 weight ratio in continuous operation in a pilot-scale slurry hydrocracker in order to investigate the impact of process parameters on product quality and process performance. Mass balances together with product characterization were used to investigate product yields, product composition, and hydrodeoxygenation. Best conversion and hydrodeoxygenation of the fast pyrolysis bio-oil was achieved using an unsupported catalyst loading of 900 ppm Mo with either a low temperature (410 °C) and long residence time (2 h) or higher temperature (435 °C) and shorter residence time (1 h). These settings resulted in about 94% hydrodeoxygenation but also led to highest yield of biogenic carbon to gas phase (40-43 wt %) and lowest yield of biogenic carbon to oil fractions (53-56 wt %) as well as the water fraction (3-5 wt %). Successfully, coke yield remained low at around 0.07-0.10 wt % for all performed runs, which was comparable to the insoluble particle content in the feed due to the presence of particles in the untreated fast pyrolysis bio-oil. Co-processing pyrolysis oil with fossil oil in a slurry hydrocracker seems to be a robust process with regard to coke formation, which should lead to reduced plugging issues compared to fixed bed hydrotreaters. Although this study gives a brief understanding of the effect of process parameters on the processing of fast pyrolysis bio-oil, further research is required to find optimal process parameters and to fully comprehend the possibilities and limitations for production of transportation fuels from fast pyrolysis bio-oil using this technology.
7.	Bergvall, Niklas, et al. (författare) Corefining of Fast Pyrolysis Bio-Oil with Vacuum Residue and Vacuum Gas Oil in a Continuous Slurry Hydrocracking Process 2020 Ingår i: Energy & Fuels. - : American Chemical Society. - 0887-0624 .- 1520-5029. ; 34:7, s. 8452-8465 Tidskriftsartikel (refereegranskat)abstract Integration of renewable raw materials in existing refineries is most likely the shortest way for the successful, large-scale introduction of biofuels in the transport sector in the short term and medium term. One possible renewable raw material for this application is fast pyrolysis bio-oil (FPBO), which in this study has been coprocessed (at 0 and 20 wt %) with vacuum residue (VR, 50 wt %) and vacuum gas oil (VGO, balance) in a continuous, as well as a semibatch, slurry hydrocracking process. Experiments both with and without FPBO were performed at 450°C and 150 bar with a continuous hydrogen flow through the reactor. Oil-soluble molybdenum hexacarbonyl and molybdenum 2-ethylhexanoate were used as catalyst precursors, to be sulfided in situ. The continuous trials resulted in reactor walls completely free of coking, and they resulted in a low overall coke yield (about 1 wt %). The hydrodeoxygenation reached almost 92%, and the total acid number was reduced by nearly 99% in the FPBO experiment A mass balance of the renewable carbon from FPBO, based on the performed experiments, showed that the fossil CO2 emissions can be lowered by 1.35 kg per kg of processed FPBO if all renewable carbon in gaseous and liquid hydrocarbons is used to replace its fossil counterparts, and all methane formed from FPBO is used to produce hydrogen. Semibatch experiments gave less successful results when upgrading FPBO-containing feedstock, with a high coke yield (8 wt %) as well as a high gas yield (24 wt %). The results of this study demonstrate that FPBO can be successfully coprocessed with heavy fossil oils in a continuous slurry hydrocracking process without neg. affecting the processing of the fossil components of the feed and that a continuous process is preferred over batch or semibatch processes when studying coprocessing of bio-oils.
8.	Bergvall, Niklas, et al. (författare) Slurry Hydroconversion of Solid Kraft Lignin to Liquid Products Using Molybdenum- and Iron-Based Catalysts 2022 Ingår i: Energy & Fuels. - : American Chemical Society (ACS). - 1520-5029 .- 0887-0624. ; 36:17, s. 10226-10242 Tidskriftsartikel (refereegranskat)abstract Kraft lignin is an abundantly available and largely underutilized renewable material with potential for production of biobased fuels and chemicals. This study reports the results of a series of slurry hydroprocessing experiments with the aim of converting solid Kraft lignin to liquid products suitable for downstream refining in more conventional reactors. Experiments reported in this study were conducted by feeding a lignin slurry to an already hot, liquid-filled reactor to provide momentaneous heating of the lignin to the reaction temperature. This modified batch procedure provided superior results compared to the regular batch experiments, likely since unwanted repolymerization and condensation reactions of the lignin during the heating phase was avoided, and was therefore used for most of the experiments reported. Experiments were performed using both an unsupported Mo-sulfide catalyst and Fe-based catalysts (bauxite and hematite) at varied reaction temperatures, pressures, and catalyst loadings. The use of Mo-sulfide (0.1% Mo of the entire feed mass) at 425 °C and 50 bar resulted in complete conversion of the Kraft lignin to nonsolid products. Very high conversions (>95%) could also be achieved with both sulfided bauxite or hematite at the same temperature and pressure, but this required much higher catalyst loadings (6.25% bauxite or 4.3% hematite of the total feed mass), and around 99% conversion could be achieved at higher temperatures but at the expense of much higher gas yields. Although requiring much higher loadings, the results in this study suggest that comparatively nonexpensive Fe-based catalysts may be an attractive alternative for a slurry-based process aimed at the hydroconversion of solid lignin to liquid products. Possible implementation strategies for a slurry-based hydroconversion process are proposed and discussed.
9.	Bergvall, Niklas, et al. (författare) Upgrading of fast pyrolysis bio-oils to renewable hydrocarbons using slurry- and fixed bed hydroprocessing 2024 Ingår i: Fuel processing technology. - : Elsevier B.V.. - 0378-3820 .- 1873-7188. ; 253 Tidskriftsartikel (refereegranskat)abstract Liquefaction of lignocellulosic biomass through fast pyrolysis, to yield fast pyrolysis bio-oil (FPBO), is a technique that has been extensively researched in the quest for finding alternatives to fossil feedstocks to produce fuels, chemicals, etc. Properties such as high oxygen content, acidity, and poor storage stability greatly limit the direct use of this bio-oil. Furthermore, high coking tendencies make upgrading of the FPBO by hydrodeoxygenation in fixed-bed bed hydrotreaters challenging due to plugging and catalyst deactivation. This study investigates a novel two-step hydroprocessing concept; a continuous slurry-based process using a dispersed NiMo-catalyst, followed by a fixed bed process using a supported NiMo-catalyst. The oil product from the slurry-process, having a reduced oxygen content (15 wt%) compared to the FPBO and a comparatively low coking tendency (TGA residue of 1.4 wt%), was successfully processed in the downstream fixed bed process for 58 h without any noticeable decrease in catalyst activity, or increase in pressure drop. The overall process resulted in a 29 wt% yield of deoxygenated oil product (0.5 wt% oxygen) from FPBO with an overall carbon recovery of 68%.
10.	Braun, Stefan, et al. (författare) Wafer-Scale Manufacturing of Bulk Shape-Memory-Alloy Microactuators Based on Adhesive Bonding of Titanium-Nickel Sheets to Structured Silicon Wafers 2009 Ingår i: Journal of microelectromechanical systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 1057-7157 .- 1941-0158. ; 18:6, s. 1309-1317 Tidskriftsartikel (refereegranskat)abstract This paper presents a concept for the wafer-scale manufacturing of microactuators based on the adhesive bonding of bulk shape-memory-alloy (SMA) sheets to silicon microstructures. Wafer-scale integration of a cold-state deformation mechanism is provided by the deposition of stressed films onto the SMA sheet. A concept for heating of the SMA by Joule heating through a resistive heater layer is presented. Critical fabrication issues were investigated, including the cold-state deformation, the bonding scheme and related stresses, and the titanium-nickel (TiNi) sheet patterning. Novel methods for the transfer stamping of adhesive and for the handling of the thin TiNi sheets were developed, based on the use of standard dicing blue tape. First demonstrator TiNi cantilevers, wafer-level adhesively bonded on a microstructured silicon substrate, were successfully fabricated and evaluated. Intrinsically stressed silicon dioxide and silicon nitride were deposited using plasma-enhanced chemical vapor deposition to deform the cantilevers in the cold state. Tip deflections for 2.5-mm-long cantilevers in cold/hot state of 250/70 and 125/28 mu m were obtained using silicon dioxide and silicon nitride, respectively. The bond strength proved to be stronger than the force created by the 2.5-mm-long TiNi cantilever and showed no degradation after more than 700 temperature cycles. The shape-memory behavior of the TiNi is maintained during the integration process.
11.	Carannante, Valentina, et al. (författare) Generation of tumor spheroids in microwells to study NK cell cytotoxicity, infiltration and phenotype 2023 Ingår i: Methods in Cell Biology. - : Elsevier BV. - 0091-679X. ; , s. 195-208 Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract The development of new immunotherapeutic drugs and combinatorial strategies requires the implementation of novel methods to test their efficacy in vitro. Here, we present a series of miniaturized in vitro assays to assess immune cell cytotoxic activity, infiltration, and phenotype in renal carcinoma spheroids with the use of a recently developed multichambered microwell chip. We provide protocols for tumor spheroid formation, NK cell culture, fluorescence labelling and imaging of live or fixed cells directly in the chip together with data analysis.
12.	da Silva Granja, Carlos, et al. (författare) Characterisation of particle-surface interactions via anharmonic acoustic transduction 2018 Ingår i: Sensors and actuators. B, Chemical. - : Elsevier. - 0925-4005 .- 1873-3077. ; 272, s. 175-184 Tidskriftsartikel (refereegranskat)
13.	de Sousa, Nuno Rufino, et al. (författare) A fieldable electrostatic air sampler enabling tuberculosis detection in bioaerosols 2020 Ingår i: Tuberculosis. - : Elsevier BV. - 1472-9792 .- 1873-281X. ; 120 Tidskriftsartikel (refereegranskat)abstract Tuberculosis (TB) infects about 25% of the world population and claims more human lives than any other infectious disease. TB is spread by inhalation of aerosols containing viable Mycobacterium tuberculosis expectorated or exhaled by patients with active pulmonary disease. Air-sampling technology could play an important role in TB control by enabling the detection of airborne M. tuberculosis, but tools that are easy to use and scalable in TB hotspots are lacking. We developed an electrostatic air sampler termed the TB Hotspot DetectOR (THOR) and investigated its performance in laboratory aerosol experiments and in a prison hotspot of TB transmission. We show that THOR collects aerosols carrying microspheres, Bacillus globigii spores and M. bovis BCG, concentrating these microparticles onto a collector piece designed for subsequent detection analysis. The unit was also successfully operated in the complex setting of a prison hotspot, enabling detection of a molecular signature for M. tuberculosis in the cough of inmates. Future deployment of this device may lead to a measurable impact on TB case-finding by screening individuals through the aerosols they generate.
14.	Dimitriadis, Athanasios, et al. (författare) Biomass conversion via ablative fast pyrolysis and hydroprocessing towards refinery integration : Industrially relevant scale validation 2023 Ingår i: Fuel. - : Elsevier Ltd. - 0016-2361 .- 1873-7153. ; 332 Tidskriftsartikel (refereegranskat)abstract Reducing the use of fossil fuels is an ongoing and important effort considering the environmental impact and depletion of fossil-based resources. The combination of ablative fast pyrolysis and hydroprocessing is explored as a pathway allowing bio-based intermediates (BioMates) integration in underlying petroleum refineries. The proposed technology is validated in industrially relevant scale, identifying pros and cons towards its commercialization. Straw from wheat, rye and barley was fed to ablative fast pyrolysis rendering Fast Pyrolysis Bio-Oil (FPBO) as the main product. The FPBO was stabilized via slurry hydroprocessing, rendering a stabilized FPBO (sFPBO) with 49 % reduced oxygen content, 71 % reduced carbonyl content and 49 % reduced Conradson carbon residue. Fixed bed catalytic hydroprocessing of sFPBO resulted in the production of BioMates, a high bio-content product to be co-fed in established refinery units. Compared to the starting biomass, BioMates has 83.6 wt% C content increase, 92.5 wt% O content decrease, 93.0 wt% water content decrease, while the overall technology has 20 wt% conversion yield (32 wt% carbon yield) from biomass to BioMates. © 2022 The Author(s)
15.	Eriksson, Louise, 1973-, et al. (författare) The importance of structural, situational, and psychological factors for involving hunters in the adaptive flyway management of geese 2023 Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 13:1 Tidskriftsartikel (refereegranskat)abstract Adaptive flyway management of superabundant geese is emerging as a strategy to reduce damage to agricultural crops and other ecosystem disservices, while also ensuring sustainable use and conservation objectives. Given the calls for intensified hunting as part of flyway management in Europe, we need to increase the understanding of structural, situational, and psychological factors important for goose hunting among hunters. Our survey data, retrieved in southern Sweden, showed a higher potential to intensify hunting among goose hunters than other hunters. In response to hypothetical policy instruments (including regulations, collaborative, and others), hunters declared a minor increase in their intention to hunt geese, with the greatest expected increase among goose hunters should the hunting season be extended. Situational factors (e.g., access to hunting grounds) were associated with goose hunting (frequency, bag size, and intention to increase hunting). In addition, controlled motivation (derived from external pressures or to avoid guilt) and more importantly autonomous motivation (due to hunting being enjoyable or valuable) were along with goose hunter identity positively associated with goose hunting. Hunters’ involvement in flyway management may be encouraged by using policy instruments to remove situational barriers and facilitate their autonomous motivation.
16.	Errando-Herranz, Carlos, et al. (författare) Integration of microfluidics with grating coupled silicon photonic sensors by one-step combined photopatterning and molding of OSTE 2013 Ingår i: Optics Express. - : Optical Society of America. - 1094-4087. ; 21:18, s. 21293-21298 Tidskriftsartikel (refereegranskat)abstract We present a novel integration method for packaging silicon photonic sensors with polymer microfluidics, designed to be suitable for wafer-level production methods. The method addresses the previously unmet manufacturing challenges of matching the microfluidic footprint area to that of the photonics, and of robust bonding of microfluidic layers to biofunctionalized surfaces. We demonstrate the fabrication, in a single step, of a microfluidic layer in the recently introduced OSTE polymer, and the subsequent unassisted dry bonding of the microfluidic layer to a grating coupled silicon photonic ring resonator sensor chip. The microfluidic layer features photopatterned through holes (vias) for optical fiber probing and fluid connections, as well as molded microchannels and tube connectors, and is manufactured and subsequently bonded to a silicon sensor chip in less than 10 minutes. Combining this new microfluidic packaging method with photonic waveguide surface gratings for light coupling allows matching the size scale of microfluidics to that of current silicon photonic biosensors. To demonstrate the new method, we performed successful refractive index measurements of liquid ethanol and methanol samples, using the fabricated device. The minimum required sample volume for refractive index measurement is below one nanoliter.
17.	Errando-Herranz, Carlos, et al. (författare) Integration Of Polymer Microfluidic Channels, Vias, And Connectors With Silicon Photonic Sensors By One-Step Combined Photopatterning And Molding Of OSTE 2013 Ingår i: Proceedings of the 2013 17th International Solid-State Sensors, Actuators and Microsystems Conference (Transducers). - : IEEE conference proceedings. ; , s. 1613-1616 Konferensbidrag (refereegranskat)abstract We demonstrate a method for the fast and simple packaging of silicon sensors into a microfluidic package consisting of the recently introduced {OSTE} polymer. The microfluidic layer is first microstructured and thereafter dry-bonded to a silicon photonic sensor, in a process compatible with wafer-level production, and with the entire packaging process lasting only 10 minutes. The fluidic layer combines molded microchannels and fluidic (Luer) connectors with photopatterned through-holes (vias) for optical fiber probing and fluid connections. All the features are fabricated in a single photocuring step. We report measurements with an integrated silicon photonic {Mach-Zehnder} interferometer refractive index sensor packaged by these means.
18.	Errando-Herranz, Carlos, et al. (författare) Integration of polymer microfluidics with silicon photonic biosensors by one-step combined photopatterning and molding of OSTE 2013 Konferensbidrag (refereegranskat)abstract We demonstrate a method for the fast and simple packaging of silicon sensors into a microfluidic package consisting of the recently introduced {OSTE} polymer. The microfluidic layer is first microstructured and thereafter dry-bonded to a silicon photonic sensor, in a process compatible with wafer-level production, and with the entire packaging process lasting only 10 minutes. The fluidic layer combines molded microchannels and fluidic (Luer) connectors with photopatterned through-holes (vias) for optical fiber probing and fluid connections. All the features are fabricated in a single photocuring step. We report measurements with an integrated silicon photonic {Mach-Zehnder} interferometer refractive index sensor packaged by these means.
19.	Frisk, Thomas, et al. (författare) A miniaturised QCM-based integrated electronic nose system 2007 Konferensbidrag (övrigt vetenskapligt/konstnärligt)
20.	Frisk, Thomas, et al. (författare) An integrated QCM-based narcotics sensing microsystem 2008 Ingår i: Lab on a Chip. - : RSC Publishing. - 1473-0197 .- 1473-0189. ; 8:10, s. 1648-1657 Tidskriftsartikel (refereegranskat)abstract We present the design, fabrication and successful testing of a 14 x 14 x 4 mm(3) integrated electronic narcotics sensing system which consists of only four parts. The microsystem absorbs airborne narcotics molecules and performs a liquid assay using an integrated quartz crystal microbalance (QCM). A vertically conductive double-sided adhesive foil (VCAF) was used and studied as a novel material for LOC and MEMS applications and provides easy assembly, electrical contacting and liquid containment. The system was tested for measuring cocaine and ecstasy, with successful detection of amounts as small as 100 ng and 200 ng, respectively These levels are of interest in security activities in customs, prisons and by the police.
21.	Granja, C. D. S., et al. (författare) A quartz crystal resonator for cellular phenotyping 2020 Ingår i: Biosensors and Bioelectronics: X. - : Elsevier Ltd. - 2590-1370. ; 6 Tidskriftsartikel (refereegranskat)abstract Cell therapy manufacturing is limited by lack of online tools capable of realtime in-process monitoring, particularly of simultaneous changes in multiple orthogonal (mutually independent) parameters. Here, we studied changes in CD36 expression, number density and size (area) of erythroblasts through different stages of erythropoiesis in vitro using a quartz crystal resonator (QCR), integrated with a microscope, and flow cytometry in parallel. An analytical model was developed extending the Kanazawa-Gordon theory. Based on this model, independent correlations were established between changes in each QCR parameter, dissipation (ΔΓ) and resonance frequency (−Δf0), and CD36 expression (from flow cytometry) and cell area (from microscope). The correlation functions were used to derive an acoustic signature (−ΔΓ/Δf0) of the differentiation process that uniquely mapped the relative changes in CD36 expression and late-stage enucleation-related deviations. A method to quantify relative changes in cell area purely from the acoustic parameters was also proposed. This work demonstrated for the first time the potential of an electromechanical tool for online monitoring of concurrently varying orthogonal phenotypic parameters in cell therapy manufacturing.
22.	Guha, Arnab, et al. (författare) Direct detection of small molecules using a nano-molecular imprinted polymer receptor and a quartz crystal resonator driven at a fixed frequency and amplitude 2020 Ingår i: Biosensors & bioelectronics. - : ELSEVIER ADVANCED TECHNOLOGY. - 0956-5663 .- 1873-4235. ; 158 Tidskriftsartikel (refereegranskat)abstract Small molecule detection is of wide interest in clinical and industrial applications. However, its accessibility is still limited as miniaturisation and system integration is challenged in reliability, costs and complexity. Here we combined a 14.3 MHz quartz crystal resonator (QCR), actuated and analysed using a fixed frequency drive (FFD) method, with a nanomolecular imprinted polymer for label-free, realtime detection of N-hexanoyl-L-homoserine lactone (199 Da), a gram-negative bacterial infection biomarker. The lowest concentration detected (1 mu M) without any optimisation was comparable with that of a BIAcore SPR system, an expensive laboratory gold standard, with significant enhancement in sensitivity and specificity beyond the state-of-the-art QCR. The analytical formula-based FFD method can potentially allow a multiplexed "QCR-on-chip" technology, bringing a paradigm shift in speed, accessibility and affordability of small molecule detection.
23.	Guha, Arnab, et al. (författare) Measurement of protein binding with vastly improved time resolution using a quartz crystal microbalance driven at a fixed frequency 2017 Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Introduction: Quartz crystal microbalance (QCM) is commonly used to study biomolecular binding by measuring shifts in resonance frequency of a quartz-crystal-oscillator. However, the currently used methods like impedance analysis or QCM-D, which require repeated sweeps or ringing, are limited in time resolution (~1 second) due to the need for averaging. This restricts our ability to study transient biomolecular processes, which occur in sub-millisecond time scale. A novel technique has been reported here that allows quantification of resonance frequency of a quartz-crystal-oscillator with significantly improved time resolution by driving and measuring continuously at a constant frequency within the resonance bandwidth. Method: The reactive component of the experimentally obtained impedance is utilized for the estimation of resonance frequency from the Butterworth Van-dyke (BVD) model of a quartz-crystal-oscillator, assuming that changes in motional inductance and capacitance around resonance are negligible. Triplicate sets of experiments involving the binding of streptavidin with a biotin functionalized 14.3 MHz quartz oscillator surface were performed. Intermittent frequency sweeps and fixed frequency drives, both of 0.1 second duration and around 14.3 MHz, were taken at intervals of 2 minutes under the flow of phosphate-buffer-saline (PBS buffer) before and after injection of streptavidin. Results: The average shift in resonance frequency from the baseline (measurements before streptavidin injection) due to streptavidin-biotin binding, calculated from the fixed frequency drive or FFD (148 Hz) was within 1% of that estimated from the frequency sweep method by fitting the experimentally recorded impedance employing the BVD model (149 Hz). Discussion: The agreement of the FFD with conventional frequency sweep method suggests that protein binding can be quantified with reasonable accuracy from each impedance data point, which with our set-up is recorded at 30 kHz sampling rate. This gives a time resolution of 0.03 millisecond, which is about 4 orders of magnitude improvement over the state-of-the-art.
24.	Guha, Arnab, et al. (författare) Simple and ultrafast resonance frequency and dissipation shift measurements using a fixed frequency drive 2018 Ingår i: Sensors and actuators. B, Chemical. - : Elsevier. - 0925-4005 .- 1873-3077. ; 281, s. 960-970 Tidskriftsartikel (refereegranskat)abstract A new method for determination of resonance frequency and dissipation of a mechanical oscillator is presented. Analytical expressions derived using the Butterworth-Van Dyke equivalent electrical circuit allow the determination of resonance frequency and dissipation directly from each impedance datapoint acquired at a fixed amplitude and frequency of drive, with no need for numerical fitting or measurement dead time unlike the conventional impedance or ring-down analysis methods. This enables an ultrahigh time resolution and superior noise performance with relatively simple instrumentation. Quantitative validations were carried out successfully against the impedance analysis method for inertial and viscous loading experiments on a 14.3 MHz quartz crystal resonator (QCR). Resonance frequency shifts associated with the transient processes of quick needle touches on a thiol self-assembled-monolayer functionalised QCR in liquid were measured with a time resolution of 112 μs, which is nearly two orders of magnitude better than the fastest reported quartz crystal microbalance. This simple and fast fixed frequency drive (FFD) based method for determination of resonance frequency and dissipation is potentially more easily multiplexable and implementable on a single silicon chip delivering economies of scale.
25.	Guha, Arnab, et al. (författare) Simpler and faster quartz crystal microbalance for macromolecule detection using fixed frequency drive 2022 Ingår i: Sensors and actuators. B, Chemical. - : Elsevier BV. - 0925-4005 .- 1873-3077. ; 358 Tidskriftsartikel (refereegranskat)abstract Despite advancements in analytical technologies, their complexity and cost have largely restricted their application in scalable online or multiplexed measurements. Here we report a quartz crystal resonator (QCR)-based method for detection of macromolecules that allows immensely simpler and faster measurements by employing for the first time a fixed frequency drive (FFD) and analytical expressions of acoustic parameters. Using human immunoglobulin E (hIgE) as an exemplar macromolecule and an anti-hIgE aptamer functionalised on a QCR, quantitative accuracy was benchmarked against the traditional impedance analysis method. The ability of FFD to capture data over longer observation periods at significantly higher acquisition rates at a fixed amplitude showed improvement in the QCR's sensitivity and specificity of transduction. The foundations for low-cost and low power online integration and large-scale multiplexability are also discussed.
26.	Gylfason, Kristinn B., 1978-, et al. (författare) Integration of polymer based microfluidics with silicon photonics for biosensing applications 2015 Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract We present a novel integration method for packaging silicon photonic sensors with polymer microfluidics, designed to be suitable for wafer-level production. The method addresses the previously unmet manufacturing challenges of matching the microfluidic footprint area to that of the photonics, and of robust bonding of microfluidic layers to biofunctionalized surfaces. We demonstrate the fabrication, in a single step, of a microfluidic layer in the recently introduced OSTE polymer, and the subsequent unassisted dry bonding of the microfluidic layer to a grating coupled silicon photonic ring resonator sensor chip. The microfluidic layer features photopatterned through holes (vias) for optical fiber probing and fluid connections, as well as molded microchannels and tube connectors, and is manufactured and subsequently bonded to a silicon sensor chip in less than 10 minutes. Combining this new microfluidic packaging method with photonic waveguide surface gratings for light couplin g allows matching the size scale of microfluidics to that of current silicon photonic biosensors.
27.	Hill, Daniel, et al. (författare) Microfluidic and Transducer Technologies for Lab on a Chip Applications 2010 Ingår i: 2010 ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC). - : IEEE conference proceedings. - 9781424441242 ; , s. 305-307 Konferensbidrag (refereegranskat)abstract Point-of-care diagnostic devices typically require six distinct qualities: they must deliver at least the same sensitivity and selectivity, and for a cost per assay no greater than that of today's central lab technologies, deliver results in a short period of time (<15 min at GP; <2h in hospital), be portable or at least small in scale, and require no or extremely little sample preparation. State-of-the-art devices deliver information of several markers in the same measurement.
28.	Johansson, Ann-Christine, et al. (författare) Comparison of co-refining of fast pyrolysis oil from Salix via catalytic cracking and hydroprocessing 2023 Ingår i: Biomass and Bioenergy. - : Elsevier Ltd. - 0961-9534 .- 1873-2909. ; 172 Tidskriftsartikel (refereegranskat)abstract Lignocellulosic biomass from energy crops, i.e., short rotation coppice willows such as Salix spp., can be used as feedstock for production of transportation biofuels. Biomass conversion via fast pyrolysis followed by co-refining with fossil oil in existing refinery infrastructure could enable a fast introduction of large-scale production of biofuels. In this study, Salix was first liquefied using ablative fast pyrolysis in a pilot scale unit. The resulting pyrolysis oil, rich in oxygenates, was thereafter co-refined in 20 wt% ratio with fossil feedstock using two separate technologies, a fluidized catalytic cracking (FCC) laboratory unit and a continuous slurry hydroprocessing pilot plant. In the FCC route, the pyrolysis oil was cracked at 798 K using a commercial FCC catalyst at atmospheric pressure, while in the hydroprocessing route, the oil was processed at 693 K and a hydrogen pressure of 15 MPa in the presence of an unsupported molybdenum sulfide catalyst. Both routes resulted in significant deoxygenation (97 wt% versus 93 wt%). It is feasible to co-refine pyrolysis oil using both methods, the main difference being that the hydroprocessing results in a significantly higher biogenic carbon yield from the pyrolysis oil to liquid and gaseous hydrocarbon products (92 wt%) but would in turn require input of H2. In the cracking route, besides the liquid product, a significant part of the biogenic carbon ends up as gas and as coke on the catalyst. The choice of route depends, among other factors, on the available amount of bio-oil and refining infrastructures. © 2023 The Authors
29.	Karlsson, J. Mikael, et al. (författare) On-Chip Liquid Degassing With Low Water Loss 2010 Ingår i: Proceedings Micro Total Analysis Systems (μTAS) 2010. - Groningen : CBMS. - 9780979806438 ; , s. 1790-1792 Konferensbidrag (refereegranskat)abstract We present a novel approach for actively degassing liquid and removing trapped air bubbles in microfluidic devices.In our approach, an integrated gas permeable membrane, consisting of a structurally supporting PDMS layer that is covered with a thin Teflon® AF 1600 film, separates the on-chip liquid from an on-chip low-vacuum chamber. Since the Teflon AF permeability is near zero for liquid water and low for vapour, air bubbles and dissolved air are removed through the membrane whilst the loss of water, ions and biomolecules in the system remains low. The system has been demonstrated at elevated temperatures and could be suitable for e.g. degassing during on-chip PCR.
30.	Khobragade, Shilpa, et al. (författare) Direct detection of whole bacteria using a nonlinear acoustic resonator 2020 Ingår i: Sensors and actuators. B, Chemical. - : Elsevier. - 0925-4005 .- 1873-3077. ; 316 Tidskriftsartikel (refereegranskat)abstract Direct detection of whole vegetative bacteria was investigated employing a quartz crystal resonator (QCR) in its nonlinear regime. Escherichia coli (E. coli) in buffer solution under flow was captured on a QCR in a microfluidic cell using a whole-cell anti-E.coli aptamer. The nonlinear distortion in QCR response due to the 'pull' from surface-bound bacteria was measured in realtime as the change in third Fourier harmonic (3f) current and compared with shifts in the traditional acoustic parameters of resonance frequency and dissipation. The change in 3f current showed superior quantitative correlation with E. coli concentrations (105-108 cfu/mL) and at least an order of magnitude better sensitivity than shifts in the traditional acoustic parameters. Most interestingly, underpinned by the strength of bacteria-QCR pull, the nonlinear acoustic principle demonstrated a unique specificity in transduction, even in a mixed sample with another gram-negative bacteria, that can supplement the specificity of the bioreceptors. An analytical expression was derived to quantitatively relate the competing influence of shifts in dissipation and nonlinearity coefficient of the QCR on the change in 3f current. This study demonstrates the potential for reliable direct readout of bioreceptor-mediated binding of whole vegetative bacteria from complex samples using a nonlinear acoustic resonator.
31.	Leirs, Karen, et al. (författare) Rapid ultra-sensitive detection of influenza A nucleoproteins using a microfluidic nonlinear acoustic sensor 2014 Konferensbidrag (refereegranskat)
32.	Leirs, Karen, et al. (författare) Screening of antibodies for the development of a fast and sensitivie influenza : A nucleoprotein detection on a nonlinear acoustic sensor 2014 Konferensbidrag (refereegranskat)
33.	Lindgren, Charlie (författare) Voluntary Information Sharing, Retail Pricing and Firm Performance 2021 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Online information sharing by firms has created an unprecedented amount of data to analyze by researchers. While conclusions from research should be drawn with basis in sound theory, there has also emerged a need to supplement these theoretical considerations with advanced data collection, storage and analysis as well as reporting to decisionmakers. As such, the emergence of the research field of microdata analysis has given aid in the process of gathering large quantities of data and managing databases, analyzing said data with knowledge in advanced areas, e.g., statistical inference, machine learning, artificial intelligence and the like, and presenting the results for decisionmakers and stakeholders in a clear, coherent way while also stating economic consequences to enable decision-making. This dissertation consists of five individual papers contributing to this field of research, and in the process answering a set of questions related to voluntary information sharing, retail pricing, and firm performance.In the first paper, a large-scale data collection of corporate social responsibility reports was coupled with state-of-the-art topic modelling analysis to answer the question who the intended users of these reports are, and the results show that the shareholder perspective is more prominent rather than the stakeholder perspective. The second paper empirically shows the value of having lowest price or highest ratings on a price comparison website, with the former being found to have a profound impact on demand, while the effect of the latter is more unclear. The third paper relies on time series clustering analysis to test if intertemporal price discrimination is the cause of remaining price dispersion in low search cost markets. The empirical evidence rejects an established theory of explaining price dispersion in a wide range of markets characterized by low search costs. The fourth paper provides an investigation into how the increased use of a price comparison website affect pricing. It is found that an increased use of the platform and number of retailers entering lead to a reduction in average prices with substantial consumer savings as the general outcome. Following the results of the third paper, a more likely model to explain the persistent price dispersion in low search cost markets is also presented. The fifth and final paper combines two datasets with rigorous statistical analysis to answer why firms compete on price comparison websites, despite the threat of increased competition and reductions in prices. The results show that retailers competing on price comparison websites increase their productivity which creates increased profits that are shared between shareholders and employees. The different types of information sharing studied in this thesis is thus found to have profound impact on consumers, firms and society at large.
34.	Månsson, Johan, et al. (författare) Understanding and overcoming obstacles in adaptive management 2024 Ingår i: Trends in Ecology and Evolution. - : Elsevier Ltd.. - 0169-5347 .- 1872-8383. ; 38:1, s. 55-71 Forskningsöversikt (refereegranskat)abstract Adaptive management (AM) is widely promoted to improve management of natural resources, yet its implementation is challenging. We show that obstacles to the implementation of AM are related not only to the AM process per se but also to external factors such as ecosystem properties and governance systems. To overcome obstacles, there is a need to build capacities within the AM process by ensuring adequate resources, management tools, collaboration, and learning. Additionally, building capacities in the legal and institutional frames can enable the necessary flexibility in the governance system. Furthermore, in systems experiencing profound changes in wildlife populations, building such capacities may be even more critical as more flexibility will be needed to cope with increased uncertainty and changed environmental conditions.
35.	Nordlund, Maria, et al. (författare) Inledning : till kapitel 8 och 9 om bedömningsstöd 2019 Ingår i: Bedömning i matematik. - Stockholm : Institutionen för matematikämnets och naturvetenskapsämnenas didaktik. - 9789197951661 Bokkapitel (övrigt vetenskapligt/konstnärligt)
36.	Pardon, Gaspard, 1983-, et al. (författare) Aerosol sampling using an electrostatic precipitator integrated with a microfluidic interface 2015 Ingår i: Sensors and actuators. B, Chemical. - : Elsevier. - 0925-4005 .- 1873-3077. ; 212, s. 344-352 Tidskriftsartikel (refereegranskat)abstract In this work, the development of a point-of-care (PoC) system to capture aerosol from litres of air directly onto a microfluidic lab-on-chip for subsequent analysis is addressed. The system involves an electrostatic precipitator that uses corona charging and electrophoretic transport to capture aerosol droplets onto a microfluidic air-to-liquid interface for downstream analysis. A theoretical study of the governing geometric and operational parameters for optimal electrostatic precipitation is presented. The fabrication of an electrostatic precipitator prototype and its experimental validation using a laboratory-generated aerosolized dye is described. Collection efficiencies were comparable to those of a state-of-the-art Biosampler impinger, with the significant advantage of providing samples that are at least 10 times more concentrated. Finally, we discuss the potential of such a system for breath-based diagnostics.
37.	Pingen, Katrin, et al. (författare) High growth rate magnetron sputter epitaxy of GaN using a solid Ga target 2024 Ingår i: Vacuum. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0042-207X .- 1879-2715. ; 220 Tidskriftsartikel (refereegranskat)abstract Magnetron sputter epitaxy (MSE) is a promising processing route for group-III nitride semiconductors, with the potential to enable high-quality and low cost GaN growth for widespread use. However, fundamental techno-logical hurdles must be overcome to enable the adoption of MSE in industrial production. Here, we present a new UHV-compatible magnetron design with high-performance cooling, enabling high GaN growth rates at high growth temperatures using a solid Ga target. The magnetron is tested with a wide range of process parameters and a stable process is feasible while maintaining the solid state of the Ga target. High GaN growth rates of up to 5 mu m/h are achieved at room temperature and a growth rate of 4 mu m/h at high temperature, which is one order of magnitude higher compared to MSE with a liquid target. We grow GaN on c-plane sapphire substrates and show the impact of partial pressure ratio and target-to-substrate distance (TSD) on growth rate, film morphology and crystal quality of GaN films with scanning electron microscopy and X-ray diffraction. While the growth rate and film morphology are strongly impacted by the process parameter variation, the crystal quality is further impacted by the overall film thickness. For a 2 mu m thick GaN film a full width at half maximum of X-ray rocking curve (omega-FWHM) of GaN 10 1 1 reflection of 0.32 degrees is achieved. We demonstrate a process window for growth of dense and smooth GaN films with high crystal quality using low N2 flow rates and high TSD. By introducing a 20 nm AlN nucleation layer prior to the growth of 390 nm GaN, the omega-FWHM of GaN 0002 reflection of 0.19 degrees is achieved. The epitaxially grown crystalline structure is precisely examined by transmission electron microscopy.
38.	Prager, Isabel, et al. (författare) NK cells switch from granzyme B to death receptor–mediated cytotoxicity during serial killing 2019 Ingår i: Journal of Experimental Medicine. - : Rockefeller University Press. - 0022-1007 .- 1540-9538. ; 7:9, s. 2113-2127 Tidskriftsartikel (refereegranskat)abstract NK cells eliminate virus-infected and tumor cells by releasing cytotoxic granules containing granzyme B (GrzB) or by engaging death receptors that initiate caspase cascades. The orchestrated interplay between both cell death pathways remains poorly defined. Here we simultaneously measure the activities of GrzB and caspase-8 in tumor cells upon contact with human NK cells. We observed that NK cells switch from inducing a fast GrzB-mediated cell death in their first killing events to a slow death receptor–mediated killing during subsequent tumor cell encounters. Target cell contact reduced intracellular GrzB and perforin and increased surface-CD95L in NK cells over time, showing how the switch in cytotoxicity pathways is controlled. Without perforin, NK cells were unable to perform GrzB-mediated serial killing and only killed once via death receptors. In contrast, the absence of CD95 on tumor targets did not impair GrzB-mediated serial killing. This demonstrates that GrzB and death receptor–mediated cytotoxicity are differentially regulated during NK cell serial killing.
39.	Samel, Björn, et al. (författare) A laterally operating liquid aspiration and dispensing unit based on an expanding PDMS composite 2007 Ingår i: Micro Total Analysis Systems (muTAS). ; , s. 530-532 Konferensbidrag (refereegranskat)
40.	Samel, Björn, et al. (författare) Liquid Aspiration and Dispensing Based on an Expanding PDMS Composite 2008 Ingår i: Journal of microelectromechanical systems. - : IEEE Press. - 1057-7157 .- 1941-0158. ; 17:5, s. 1254-1262 Tidskriftsartikel (refereegranskat)abstract In this paper, we present the development of active liquid aspiration and dispensing units designed for vertical, as well as lateral, liquid aspiration. The devices are based on a single-use thermally expanding polydimethylsiloxane (PDMS) composite, which allows altering its surface topography by means of individually addressable integrated heaters. Devices are designed in order to create an enclosed cavity in the system, due to locally expanding the initially unstructured composite. This enables negative volume displacement and leads to the event of liquid aspiration. To enable this device functionality, two different techniques of selectively creating permanent PDMS bonds have been developed. One approach utilizes the plasma-assisted PDMS bonding technique, together with a patterned antistiction layer to form reversibly, as well as irreversibly, bonded regions. Another approach utilizes microcontact printing of PDMS curing agent, which serves as a patterned intermediate layer for adhesive bonding. Fabricated prototype devices successfully demonstrated the aspiration and release of liquid volumes ranging from 28 to 815 nL. The devices are entirely fabricated from low-cost materials, using wafer-level processes only and do not require external means for liquid actuation.
41.	Sandoz, Patrick, et al. (författare) Modulation of lytic molecules restrain serial killing in γδ T lymphocytes 2023 Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 14:1 Tidskriftsartikel (refereegranskat)abstract γδ T cells play a pivotal role in protection against various types of infections and tumours, from early childhood on and throughout life. They consist of several subsets characterised by adaptive and innate-like functions, with Vγ9Vδ2 being the largest subset in human peripheral blood. Although these cells show signs of cytotoxicity, their modus operandi remains poorly understood. Here we explore, using live single-cell imaging, the cytotoxic functions of γδ T cells upon interactions with tumour target cells with high temporal and spatial resolution. While γδ T cell killing is dominated by degranulation, the availability of lytic molecules appears tightly regulated in time and space. In particular, the limited co-occurrence of granzyme B and perforin restrains serial killing of tumour cells by γδ T cells. Thus, our data provide new insights into the cytotoxic arsenal and functions of γδ T cells, which may guide the development of more efficient γδ T cell based adoptive immunotherapies.
42.	Sandström, Camilla, Professor, 1967-, et al. (författare) Removing obstacles to AM should still be the focus : a reply to Dickie et al 2023 Ingår i: Trends in Ecology and Evolution. - : Elsevier Ltd.. - 0169-5347 .- 1872-8383. ; 38:6, s. 507-508 Tidskriftsartikel (refereegranskat)
43.	Sandström, Niklas, et al. (författare) Batch fabrication of polymer microfluidic cartridges for QCM sensor packaging by direct bonding 2017 Ingår i: Journal of Micromechanics and Microengineering. - : IOP Publishing. - 0960-1317 .- 1361-6439. ; 27:12 Tidskriftsartikel (refereegranskat)abstract Quartz crystal microbalance (QCM) sensing is an established technique commonly used in laboratory based life-science applications. However, the relatively complex, multi-part design and multi-step fabrication and assembly of state-of-the-art QCM cartridges makes them unsuited for disposable applications such as point-of-care (PoC) diagnostics. In this work, we present the uncomplicated manufacturing of QCMs in polymer microfluidic cartridges. Our novel approach comprises two key innovations: the batch reaction injection molding of microfluidic parts; and the integration of the cartridge components by direct, unassisted bonding. We demonstrate molding of batches of 12 off-stoichiometry thiol-ene epoxy polymer (OSTE+) polymer parts in a single molding cycle using an adapted reaction injection molding process; and the direct bonding of the OSTE+ parts to other OSTE+ substrates, to printed circuit boards, and to QCMs. The microfluidic QCM OSTE+ cartridges were successfully evaluated in terms of liquid sealing as well as electrical properties, and the sensor performance characteristics are on par with those of commercially available QCM biosensor cartridge.
44.	Sandström, Niklas, 1981-, et al. (författare) Electrohydrodynamic Enhanced Transport and Trapping of Airborne Particles to a Microfluidic Air-Liquid Interface 2008 Ingår i: Micro System Workshop 2008. Konferensbidrag (övrigt vetenskapligt/konstnärligt)
45.	Sandström, Niklas, et al. (författare) ELECTROHYDRODYNAMIC ENHANCED TRANSPORT AND TRAPPING OF AIRBORNE PARTICLES TO A MICROFLUIDIC AIR-LIQUID INTERFACE 2008 Ingår i: 21st IEEE International Conference on Micro Electro Mechanical Systems (IEEE MEMS 2008). - : IEEE conference proceedings. - 9781424417926 ; , s. 595-598 Konferensbidrag (refereegranskat)abstract We introduce a novel approach for greatly improved transport and trapping of airborne sample to a microfluidic analysis system by integrating an electrohydrodynamic (EHD) air pump with a microfluidic air-liquid interface. In our system, a negative corona discharge partially ionizes the air around a sharp electrode tip while the electrostatic field accelerates airborne particles towards an electrically grounded liquid surface, where they absorb. The air-liquid interface is fixated at the microscale pores of a perforated silicon diaphragm, each pore functioning as a static Laplace valve. Our system was experimentally tested using airborne smoke particles of ammonium chloride and aqueous salt solution as the liquid. We measured that EHD enhanced transport of the particles from the air into the liquid is enhanced over 130 times compared to passive trapping.
46.	Sandström, Niklas, et al. (författare) FULL WAFER INTEGRATION OF SHAPE MEMORY ALLOY MICROACTUATORS USING ADHESIVE BONDING 2009 Ingår i: 15th IEEE International Conference on Solid-State Sensors, Actuators and Microsystems (IEEE TRANSDUCERS 2009). - : IEEE conference proceedings. - 9781424441938 ; , s. 845-848 Konferensbidrag (refereegranskat)abstract This paper presents the wafer-scale manufacturing of microactuators based on bulk shape memory alloy material integrated using adhesive bonding. The work addresses key technical challenges related to the wafer-scale fabrication of bulk SMA micro actuators, including wafer-scale integration of patterned SMA sheets to structured Si wafers and the integration of cold state reset layers to the microactuators. Contact printing of an adhesive polymer ensures a selective bonding when transferring full SMA sheets to silicon structures on a patterned wafer. The stressed films deposited on top of the SMA microactuator ensure a built-in reset mechanism of the actuators. The paper reports on the successful wafer-scale integration of wafer-sized SMA sheets and the wafer-scale fabrication of actuator cantilevers. First test cantilevers with a length of 2.5 mm show a stroke of approx. 180 ï¿œm.
47.	Sandström, Niklas, 1981- (författare) Integrating Biosensors for Air Monitoring and Breath-Based Diagnostics 2015 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract The air we breathe is the concern of all of us but nevertheless we only know very little about airborne particles, and especially which biological microorganisms they contain. Today, we live in densely populated societies with a growing number of people, making us particularly vulnerable to air transmission of pathogens. With the recent appearance of highly pathogenic types of avian influenza in southeast Asia and the seasonal outbreaks of gastroenteritis caused by the extremely contagious norovirus, the need for portable, sensitive and rapid instruments for on-site detection and monitoring of airborne pathogens is apparent.Unfortunately, the integration incompatibility between state-of-the-art air sampling techniques and laboratory based analysis methods makes instruments for in-the-field rapid detection of airborne particles an unresolved challenge.This thesis aims at addressing this challenge by the development of novel manufacturing, integration and sampling techniques to enable the use of label-free biosensors for rapid and sensitive analysis of airborne particles at the point-of-care or in the field.The first part of the thesis introduces a novel reaction injection molding technique for the fabrication of high quality microfluidic cartridges. In addition, electrically controlled liquid aspiration and dispensing is presented, based on the use of a thermally actuated polymer composite integrated with microfluidic cartridges.The second part of the thesis demonstrates three different approaches of biosensor integration with microfluidic cartridges, with a focus on simplifying the design and integration to enable disposable use of the cartridges.The third part to the thesis presents a novel air sampling technique based on electrophoretic transport of airborne particles directly to microfluidic cartridges. This technique is enabled by the development of a novel microstructured component for integrated air-liquid interfacing. In addition, a method for liquid sample mixing with magnetic microbeads prior to downstream biosensing is demonstrated.In the fourth part of the thesis, three different applications for airborne particle biosensing are introduced and preliminary experimental results are presented.
48.	Sandström, Niklas, 1981-, et al. (författare) Integration of a QCM with an OSTE cartridge 2012 Ingår i: MicroNano System Workshop 2012. - Linköping. Konferensbidrag (övrigt vetenskapligt/konstnärligt)
49.	Sandström, Niklas, 1981-, et al. (författare) Lab-on-a-chip microsystems for point-of-care diagnostics 2010 Ingår i: 1st International scientific conference on Microfluidics in bioanalytical research and diagnostics. ; , s. 34-35 Konferensbidrag (övrigt vetenskapligt/konstnärligt)
50.	Sandström, Niklas, 1981-, et al. (författare) Laser-induced deep etching of glass for live cell assays 2021 Ingår i: MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. - : Chemical and Biological Microsystems Society. ; , s. 579-580 Konferensbidrag (refereegranskat)abstract Glass materials have excellent optical and chemical properties for microscopy-based live cell assays but state-of-the-art methods for microfabrication of Lab-on-Chip (LoC) devices are often limited by either complex manufacturing and/or low quality results. In this work, we have evaluated glass microwell array chips produced using a recently introduced laser-based microfabrication method. Three different types of microwell designs have been tested for imaging and screening of on-chip cell cultures and live cell assays.

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