1. |
- Davidsson, Richard, et al.
(författare)
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Microfluidic biosensing systems - Part II. Monitoring the dynamic production of glucose and ethanol from microchip-immobilised yeast cells using enzymatic chemiluminescent mu-biosensors
- 2004
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Ingår i: Lab on a Chip. - : Royal Society of Chemistry (RSC). - 1473-0189. ; 4:5, s. 488-494
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Tidskriftsartikel (refereegranskat)abstract
- A microfluidic flow injection (muFIA) system was employed for handling and monitoring of cell-released products from living cells immobilised on silicon microchips. The dynamic release of glucose and ethanol produced from sucrose by immobilised Saccharomyces cerevisiae cells was determined using microchip biosensors (mu-biosensors) with either co-immobilised glucose oxidase-horseradish peroxidase (GOX-HRP), or alcohol oxidase-horseradish peroxidase (AOX-HRP), catalysing a series of reactions ending up with chemiluminescence (CL) generated from HRP-catalysed oxidation of luminol in presence of p-iodophenol (PIP). The yeast cells were attached by first treating them with polyethylenimine (PEI) followed by adsorption to the microchip surface. The cell loss during assaying was evaluated qualitatively using scanning electron microscopy (SEM), showing that no cells were lost after 35 min liquid handling of the cell chip at 10 mul min(-1). The enzymes were immobilised on microchips via PEI-treatment followed by glutaraldehyde (GA) activation. The GOX-HRP mu-biosensors could be used during five days without any noticeable decrease in response, while the AOX-HRP mu-biosensors showed continuously decreasing activity, but could still be used employing calibration correction. The glucose and ethanol released from the immobilised yeast chips were quantitatively monitored, by varying the incubation time with sucrose, showing the possibilities and advantages of using a microfluidic system set-up for cell-based assays.
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2. |
- Eliasson, A., et al.
(författare)
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Cyanide-insensitive respiration.
- 2003
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Ingår i: Non-Conventional Yeasts in Genetics, Biochemistry and Biotechnology (Springer Lab Manuals). - 3540442154
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Abstract is not available
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3. |
- Feng, X. M., et al.
(författare)
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Rhizopus oligosporus and yeast co-cultivation during barley tempeh fermentation-Nutritional impact and real-time PCR quantification of fungal growth dynamics
- 2007
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Ingår i: Food microbiology (Print). - London, United Kingdom : Elsevier BV. - 0740-0020 .- 1095-9998. ; 24:4, s. 393-402
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Tidskriftsartikel (refereegranskat)abstract
- Barley tempeh was produced by fermenting barley kernels with Rhizopus oligosporus. The potential of the yeasts Saccharomyces cerevisiae (three strains), S. boulardii (one strain), Pichia anomala (one strain) and Kluyveromyces lactis (one strain) to grow together with R. oligosporus during barley tempeh fermentation was evaluated. All yeast strains grew during the fermentation and even during cold storage of tempeh (P < 0.01). The growth of yeasts slightly increased the ergosterol contents, but did not influence amino acid contents and compositions, and did not reduce phytate contents. Slight increases of vitamins B6 and niacinamide, and slight decreases of B1 and biotin were observed. Quantification of fungal growth is difficult during mixed species fermentations because ergosterol is found in all fungal species, and colony-forming-unit (cfu) estimations are not reliable for R. oligosporus and other sporulating fungi. Therefore, we developed a quantitative real-time PCR method for individually quantifying S. cerevisiae and R. oligosporus growth in barley tempeh. The PCR results were highly correlated with the ergosterol content of R. oligosporus and with the number of cfu of S. cerevisiae. Thus, real-time PCR is a rapid and selective method to quantify yeasts and R. oligosporus during mixed species fermentation of inhomogenous substrate such as barley tempeh. © 2006 Elsevier Ltd. All rights reserved.
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4. |
- Hong, Q., et al.
(författare)
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Detailed Geant4 simulations of the ANITA and ANITA-CUP neutron facilities
- 2015
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Konferensbidrag (refereegranskat)abstract
- Simulations of the ANITA spallation neutron source at The Svedberg Laboratory (TSL) are described. Neutron radiation calculations show close agreement with measurements at both standard and close user positions. Gamma radiation characteristics are also predicted.
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5. |
- Lyberg, K., et al.
(författare)
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Biochemical and microbiological properties of a cereal mix fermented with whey, wet wheat distillers' grain or water at different temperatures
- 2008
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Ingår i: Animal Feed Science and Technology. - Amsterdam, Netherlands : Elsevier. - 0377-8401 .- 1873-2216. ; 144:1-2, s. 137-148
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Tidskriftsartikel (refereegranskat)abstract
- Microbiological and biochemical properties of three different liquid diets fermented at 10, 15 or 20 degrees C were studied. The liquid diets consisted of a cereal grain mix of wheat, barley and triticale, blended with whey (diet WH), wet wheat distillers' grain (diet WDG) or water (diet WAT). The diets were fermented for 5 days without disturbance, followed by 14 days of daily feed replacements, where 4/5 of the contents were replaced with fresh feed mixtures. Starting pH values were 5.1, 3.9 and 6.3 in WH, WDG and WAT, respectively. For most diets, the pH decreased to approximately 4.0 by day 5. However, the WAT diet fermented at 10 degrees C required 7 days to reach a pH of 4.0. A higher (P < 0.001) pH was seen in the WH diet fermented at 10 degrees C than in the other diets. Composition of the diets was determined during day 17-19 of fermnentation to allow the microbial populations to stabilise and to reflect conditions in practice. Lactic acid bacteria (LAB) grew in all diets during fermentation and the growth was affected by temperature and type of diet (P < 0.001), and the interaction between these two factors (P < 0.001). The highest LAB counts were found at higher temperatures in the WAT and WH diets and the lowest counts were found in diet WDG. The highest levels of acetic, succinic and propionic acids were found in diet WDG (P < 0.001). Lactic acid concentrations increased with temperature (P < 0.001) and were highest in the WAT and WH diets. In vitro digestibility of organic matter was highest for diet WH and lowest for diet WDG (P < 0.001). Inositol hexaphosphate-bound phosphorus (P) and total P in the cereal grain mix were 2.2 and 3.7 g kg(-1) dry matter, respectively. No inositol phosphate-bound P was found in any of the diets after fermentation. Some moulds, probably originating from spores in the cereal grain mix, were delected in the fermented diets, but total numbers did not increase with time. Enterobacteriaceae detected in diet WH, probably originated from the cereal grain mix and the whey. Yeasts were present in all diet ingredients. In conclusion, fermentation processes and biochemical properties differed greatly due to temperature, type of diet and the interaction of these two factors. Dietary inositol hexaphosphate was completely degraded in all fermented diets. (c) 2007 Elsevier B.V. All rights reserved.
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6. |
- Mattera, Andrea, 1985-, et al.
(författare)
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A neutron source for IGISOL-JYFLTRAP : Design and characterisation
- 2017
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Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 53:173
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Tidskriftsartikel (refereegranskat)abstract
- A white neutron source based on the Be(p,nx) reaction for fission studies at the IGISOLJYFLTRAP facility has been designed and tested. 30 MeV protons impinge on a 5mm thick water-cooled beryllium disc. The source was designed to produce at least 1012 fast neutrons/s on a secondary fission target, in order to reach competitive production rates of fission products far from the valley of stability.The Monte Carlo codes MCNPX and FLUKA were used in the design phase to simulate the neutron energy spectra. Two experiments to characterise the neutron field were performed: the first was carried out at The Svedberg Laboratory in Uppsala (SE), using an Extended-Range Bonner Sphere Spectrometer and a liquid scintillator which used the time-of-flight (TOF) method to determine the energy of the neutrons; the second employed Thin-Film Breakdown Counters for the measurement of the TOF, and activation foils, at the IGISOL facility in Jyväskylä (FI). Design considerations and the results of the two characterisation measurements are presented, providing benchmarks for the simulations.
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7. |
- Passoth, V., et al.
(författare)
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Biotechnology, physiology and genetics of the yeast Pichia anomala
- 2006
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Ingår i: FEMS yeast research (Print). - Oxon, United Kingdom : Blackwell Publishing. - 1567-1356 .- 1567-1364. ; 6:1, s. 3-13
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Forskningsöversikt (refereegranskat)abstract
- The ascomycetous yeast Pichia anomala is frequently associated with food and feed products, either as a production organism or as a spoilage yeast. It belongs to the nonSaccharomyces wine yeasts and contributes to the wine aroma by the production of volatile compounds. The ability to grow in preserved food and feed environments is due to its capacity to grow under low pH, high osmotic pressure and low oxygen tension. A new application of P. anomala is its use as a biocontrol agent, which is based on the potential to inhibit a variety of moulds in different environments. Although classified as a biosafety class-1 organism, cases of P. anomala infections have been reported in immunocompromised patients. On the other hand, P. anomala killer toxins have a potential as antimicrobial agents. The yeast can use a broad range of nitrogen and phosphor sources, which makes it a potential agent to decrease environmental pollution by organic residues from agriculture. However, present knowledge of the physiological basis of its performance is limited. Recently, the first studies have been published dealing with the global regulation of the metabolism of P. anomala under different conditions of oxygenation.
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8. |
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9. |
- Pola, A., et al.
(författare)
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Compact Thermal Neutron Sensors for Moderator-Based Neutron Spectrometers
- 2014
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Ingår i: Radiation Protection Dosimetry. - : Oxford University Press (OUP). - 0144-8420 .- 1742-3406. ; 161:1-4, s. 229-232
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Tidskriftsartikel (refereegranskat)abstract
- In the framework of the NESCOFI@BTF project of the Italian Institute of Nuclear Physics, different types of active thermal neutron sensors were studied by coupling semiconductor devices with a suitable radiator. The objective was to develop a detector of small dimensions with a proper sensitivity to use at different positions in a novel moderating assembly for neutron spectrometry. This work discusses the experimental activity carried out in the framework of the ERINDA program (PAC 3/9 2012) to characterise the performance of a thermal neutron pulse detector based on Li-6.
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10. |
- Prokofiev, Alexander V., 1963-, et al.
(författare)
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CUP–A New High-Flux Irradiation Position at the ANITA Neutron Facility at TSL
- 2014
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Ingår i: IEEE Transactions on Nuclear Science. - 0018-9499 .- 1558-1578. ; 61:4, s. 1929-1936
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Tidskriftsartikel (refereegranskat)abstract
- A new irradiation position has been constructed,characterized, and put into operation at the ANITA facility in The Svedberg Laboratory (TSL) for accelerated testing of components and systems for single event effects. Results of beam characterization measurements are reported. The energy-integrated neutron flux above 10 MeV, amounting to more than 10^7 cm^-2 s^-1 , is the highest among the facilities with atmospheric-like spectra. The employed characterization and simulation techniques are applicable for a broad class of neutron facilities.
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