| 441. |
- Jacobsen, A. S., et al.
(författare)
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Velocity-space sensitivity of neutron spectrometry measurements
- 2015
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 0029-5515 .- 1741-4326. ; 55:5
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Tidskriftsartikel (refereegranskat)abstract
- Neutron emission spectrometry (NES) measures the energies of neutrons produced in fusion reactions. Here we present velocity-space weight functions for NES and neutron yield measurements. Weight functions show the sensitivity as well as the accessible regions in velocity space for a given range of the neutron energy spectrum. Combined with a calculated fast-ion distribution function, they determine the part of the distribution function producing detectable neutrons in a given neutron energy range. Furthermore, we construct a forward model based on weight functions capable of rapidly calculating neutron energy spectra. This forward model can be inverted and could thereby be used to directly measure the fast-ion phase-space distribution functions, possibly in combination with other fast-ion diagnostics. The presented methods and results can be applied to neutron energy spectra measured by any kind of neutron spectrometer and to any neutron yield measurement.
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| 442. |
- Jacobsen, A. S., et al.
(författare)
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Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET
- 2014
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Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 85:11, s. 11E103-
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Tidskriftsartikel (refereegranskat)abstract
- The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutronemission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of ameasured time-of-flight spectrum from TOFOR.
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| 443. |
- Jacobsen, Carsten Suhr, et al.
(författare)
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Inter-laboratory testing of the effect of DNA blocking reagent G2 on DNA extraction from low-biomass clay samples
- 2018
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Here we show that a commercial blocking reagent (G2) based on modified eukaryotic DNA significantly improved DNA extraction efficiency. We subjected G2 to an inter-laboratory testing, where DNA was extracted from the same clay subsoil using the same batch of kits. The inter-laboratory extraction campaign revealed large variation among the participating laboratories, but the reagent increased the number of PCR-amplified16S rRNA genes recovered from biomass naturally present in the soils by one log unit. An extensive sequencing approach demonstrated that the blocking reagent was free of contaminating DNA, and may therefore also be used in metagenomics studies that require direct sequencing.
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| 444. |
- Jacobsen, Freja A., et al.
(författare)
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Arg Deficiency Does not Influence the Course of Myelin Oligodendrocyte Glycoprotein (MOG35-55)-induced Experimental Autoimmune Encephalomyelitis
- 2016
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Ingår i: Journal of Clinical & Cellular Immunology. - Los Angeles : OMICS. - 2155-9899. ; 7:3
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Tidskriftsartikel (refereegranskat)abstract
- Background: Inhibition of Abl kinases has an ameliorating effect on the rodent model for multiple sclerosis, experimental autoimmune encephalomyelitis, and arrests lymphocyte activation. The family of Abl kinases consists of the Abl1/Abl and Abl2/Arg tyrosine kinases. While the Abl kinase has been extensively studied in immune activation, roles for Arg are incompletely characterized. To investigate the role for Arg in experimental autoimmune encephalomyelitis, we studied disease development in Arg-/- mice.Methods: Arg-/- and Arg+/+ mice were generated from breeding of Arg+/- mice on the C57BL/6 background. Mice were immunized with the myelin oligodendrocyte glycoprotein (MOG)35-55 peptide and disease development recorded. Lymphocyte phenotypes of wild type Arg+/+ and Arg-/- mice were studied by in vitro stimulation assays and flow cytometry.Results: The breeding of Arg+/+ and Arg-/- mice showed skewing in the frequency of born Arg-/- mice. Loss of Arg function did not affect development of experimental autoimmune encephalomyelitis, but reduced the number of splenic B-cells in Arg-/- mice following immunization with MOG peptide.Conclusions: Development of MOG-induced experimental autoimmune encephalomyelitis is not dependent on Arg, but Arg plays a role for the number of B cells in immunized mice. This might suggest a novel role for the Arg kinase in B-cell trafficking or regulation. Furthermore, the results suggest that Arg is important for normal embryonic development. © 2016 Jacobsen FA, et al.
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| 445. |
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| 446. |
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| 447. |
- Jacobsen, Jens Christian Brings, et al.
(författare)
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Heterogeneity and weak coupling may explain the synchronization characteristics of cells in the arterial wall.
- 2008
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Ingår i: Philosophical transactions. Series A, Mathematical, physical, and engineering sciences. - : The Royal Society. - 1364-503X. ; 366:1880, s. 3483-502
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Tidskriftsartikel (refereegranskat)abstract
- Vascular smooth muscle cells (SMCs) exhibit different types of calcium dynamics. Static vascular tone is associated with unsynchronized calcium waves and the developed force depends on the number of recruited cells. Global calcium transients synchronized among a large number of cells cause rhythmic development of force known as vasomotion. We present experimental data showing a considerable heterogeneity in cellular calcium dynamics in the vascular wall. In stimulated vessels, some SMCs remain quiescent, whereas others display waves of variable frequency. At the onset of vasomotion, all SMCs are enrolled into synchronized oscillation.Simulations of coupled SMCs show that the experimentally observed cellular recruitment, the presence of quiescent cells and the variation in oscillation frequency may arise if the cell population is phenotypically heterogeneous. In this case, quiescent cells can be entrained at the onset of vasomotion by the collective driving force from the synchronized oscillations in the membrane potential of the surrounding cells. Partial synchronization arises with an increase in the concentration of cyclic guanosine monophosphate, but in a heterogeneous cell population complete synchronization also requires a high-conductance pathway that provides strong coupling between the cells.
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| 448. |
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| 449. |
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| 450. |
- Jacobsen, K. R., et al.
(författare)
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Voluntary ingestion of buprenorphine in mice
- 2011
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Ingår i: Animal Welfare. - 0962-7286. ; 20:4, s. 591-596
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Tidskriftsartikel (refereegranskat)abstract
- Buprenorphine is a widely used analgesic for laboratory rodents. Administration of the drug in a desirable food item for voluntary ingestion is an attractive way to administer the drug non-invasively. However, it is vital that the animals ingest the buprenorphine-food-item mix as desired. The present study investigated how readily female and male mice (Mus musculus) of two different strains consumed buprenorphine mixed in a commercially available nut paste (Nutellac (R)), and whether variation between genders and strains would affect the subsequent serum concentrations of buprenorphine. Buprenorphine at different concentrations mixed in Nutella (R) was given to male and female C57BL/6 and BALB/c mice in a complete cross-over study. Pure Nutella or buprenorphine (1.0-3.0 mg kg(-1) bodyweight [bw]) mixed in 10 g kg(-1) bw Nutella (R) were given to the mice at 1500h. The mice were video recorded until the next morning, when blood was collected by submandibular venipuncture. The concentration of buprenorphine in the Nutella (R) mix did not affect the duration of ingestion in any of the groups. However, female mice consumed the Nutella (R) significantly faster than males. Repeated exposure significantly reduced the start time of voluntary ingestion, but not the duration of eating the mixture. These differences did not however affect the serum concentration of buprenorphine measured 17 h post administration.
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