| 1. |
- Alizadehheidari, Mohammadreza, 1987, et al.
(författare)
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Nanoconfined Circular and Linear DNA: Equilibrium Conformations and Unfolding Kinetics
- 2015
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Ingår i: Macromolecules. - : American Chemical Society (ACS). - 0024-9297 .- 1520-5835. ; 48:3, s. 871-878
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Tidskriftsartikel (refereegranskat)abstract
- Studies of circular DNA confined to nanofluidic channels are relevant both from a fundamental polymer-physics perspective and due to the importance of circular DNA molecules in vivo. We here observe the unfolding of confined DNA from the circular to linear configuration as a light-induced double-strand break occurs, characterize the dynamics, and compare the equilibrium conformational statistics of linear and circular configurations. This is important because it allows us to determine to what extent existing statistical theories describe the extension of confined circular DNA. We find that the ratio of the extensions of confined linear and circular DNA configurations increases as the buffer concentration decreases. The experimental results fall between theoretical predictions for the extended de Gennes regime at weaker confinement and the Odijk regime at stronger confinement. We show that it is possible to directly distinguish between circular and linear DNA molecules by measuring the emission intensity from the DNA. Finally, we determine the rate of unfolding and show that this rate is larger for more confined DNA, possibly reflecting the corresponding larger difference in entropy between the circular and linear configurations.
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| 2. |
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| 3. |
- Karlsson, Fredrik, et al.
(författare)
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Sensor Fused Indoor Positioning Using Dual Band WiFi Signal Measurements
- 2015
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Ingår i: 2015 European Control Conference (ECC). - 9783952426937 ; , s. 1669-1672
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Konferensbidrag (refereegranskat)abstract
- In this paper, signal strengths from known WiFi access points are used together with a particle filter to perform indoor navigation. It is shown that more information is obtained by using signals of both 2.4 and 5.0 GHz, compared to using only one frequency. Thus, using both frequencies provides a more accurate positioning. The second contribution is an algorithm where WiFi measurements are combined with pedestrian dead reckoning (PDR), which is based on step counting using an accelerometer and hypotheses of the heading using a gyroscope. This was found to provide further accuracy compared to more conventional methods.
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| 4. |
- Westerlund, Fredrik, 1978, et al.
(författare)
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Fluorescence microscopy of nanochannel-confined DNA
- 2018
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Ingår i: Methods in Molecular Biology. - New York, NY : Springer New York. - 1064-3745 .- 1940-6029. ; 1665, s. 173-198
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Bokkapitel (refereegranskat)abstract
- Stretching of DNA in nanoscale confinement allows for several important studies. The genetic contents of the DNA can be visualized on the single DNA molecule level and both the polymer physics of confined DNA and also DNA/protein and other DNA/DNA-binding molecule interactions can be explored. This chapter describes the basic steps to fabricate the nanostructures, perform the experiments and analyze the data.
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| 5. |
- Aspenberg, Magnus, et al.
(författare)
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On the asymptotics of the scenery flow
- 2015
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Ingår i: Discrete and Continuous Dynamical Systems. Series A. - : American Institute of Mathematical Sciences (AIMS). - 1553-5231. ; 35:7, s. 2797-2815
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Tidskriftsartikel (refereegranskat)abstract
- We study the asymptotics of the scenery flow. We give corrected versions with proofs of a certain lemma by Hochman, and study some related phenomena.
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| 6. |
- Denny, Michael, et al.
(författare)
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Impact of closely-coupled triple-pilot and conventional double-pilot injection strategies in a LD diesel engine
- 2019
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Ingår i: Fuel. - : Elsevier BV. - 0016-2361. ; 246, s. 141-148
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Tidskriftsartikel (refereegranskat)abstract
- Three injection strategies are compared in a light-duty (LD) diesel engine at a medium load point. One strategy, representative of a Euro 6 LD injection strategy, has a double-pilot/main/single-post sequence. There is a modest temporal spacing after the first pilot and second pilot. Additional strategies add a third pilot and greatly reduce the spacing after the pilots. These pilots are referred to as being “closely-coupled” to each other and the main injection. For the double-pilot strategy, there is significant undulation of the cylinder pressure around TDC. In contrast, the closely-coupled triple-pilot strategies show notably smaller undulations in their pressure traces. Despite increases in peak pressure rise rate, combustion noise is reduced in both triple-pilot strategies. An analysis of each strategy’s heat release rate (HRR) trace shows that the close spacing of the pilot injections drastically reduces the drop in HRR between each subsequent local peak in combustion from each injection. A new metric is developed in order toquantify these drops, called the Ratio of Reduced Heat Release (RRHR). It is found that in order to reduce combustion noise, the RRHR should be minimized. Further analysis into the combustion noise shows that the occurrence frequency of the local HRR peaks matches strong frequencies responsible for combustion noise, and furthermore that the reduction in combustion noise is not due to the geometry of the combustion chamber. The modification of the HRR trace by implementing closely-coupled triple-pilot injection strategies allows combustion to be phased earlier, improving efficiency while also reducing combustion noise.
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| 7. |
- Ekström, Fredrik, et al.
(författare)
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Hausdorff dimension of random limsup sets
- 2018
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Ingår i: Journal of the London Mathematical Society. - : Wiley. - 0024-6107. ; 98:3, s. 661-686
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Tidskriftsartikel (refereegranskat)abstract
- We prove bounds for the almost sure value of the Hausdorff dimension of the limsup set of a sequence of balls in Rd whose centres are independent, identically distributed random variables. The formulas obtained involve the rate of decrease of the radii of the balls and multifractal properties of the measure according to which the balls are distributed, and generalise formulas that are known to hold for particular classes of measures.
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| 8. |
- Ekström, Fredrik, et al.
(författare)
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On the Fourier dimension and a modification
- 2015
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Ingår i: Journal of Fractal Geometry. - 2308-1309. ; 2:3, s. 309-337
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Tidskriftsartikel (refereegranskat)abstract
- We give a sufficient condition for the Fourier dimension of a countable union of sets to equal the supremum of the Fourier dimensions of the sets in the union, and show by example that the Fourier dimension is not countably stable in general. A natural approach to finite stability of the Fourier dimension for sets would be to try to prove that the Fourier dimension for measures is finitely stable, but we give an example showing that it is not in general. We also describe some situations where the Fourier dimension for measures is stable or is stable for all but one value of some parameter. Finally we propose a way of modifying the definition of the Fourier dimension so that it becomes countably stable, and show that for each s there is a class of sets such that a measure has modied Fourier dimension greater than or equal to s if and only if it annihilates all sets in the class.
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| 9. |
- Fadl, Helena, 1965-, et al.
(författare)
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Changing diagnostic criteria for gestational diabetes in Sweden-a stepped wedge national cluster randomised controlled trial-the CDC4G study protocol
- 2019
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Ingår i: Bmc Pregnancy and Childbirth. - : Springer Science and Business Media LLC. - 1471-2393. ; 19:1
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Tidskriftsartikel (refereegranskat)abstract
- Background The optimal criteria to diagnose gestational diabetes mellitus (GDM) remain contested. The Swedish National Board of Health introduced the 2013 WHO criteria in 2015 as a recommendation for initiation of treatment for hyperglycaemia during pregnancy. With variation in GDM screening and diagnostic practice across the country, it was agreed that the shift to new guidelines should be in a scientific and structured way. The aim of the Changing Diagnostic Criteria for Gestational Diabetes (CDC4G) in Sweden () is to evaluate the clinical and health economic impacts of changing diagnostic criteria for GDM in Sweden and to create a prospective cohort to compare the many long-term outcomes in mother and baby under the old and new diagnostic approaches. Methods This is a stepped wedge cluster randomised controlled trial, comparing pregnancy outcomes before and after the switch in GDM criteria across 11 centres in a randomised manner. The trial includes all pregnant women screened for GDM across the participating centres during January-December 2018, approximately two thirds of all pregnancies in Sweden in a year. Women with pre-existing diabetes will be excluded. Data will be collected through the national Swedish Pregnancy register and for follow up studies other health registers will be included. Discussion The stepped wedge RCT was chosen to be the best study design for evaluating the shift from old to new diagnostic criteria of GDM in Sweden. The national quality registers provide data on the whole pregnant population and gives a possibility for follow up studies of both mother and child. The health economic analysis from the study will give a solid evidence base for future changes in order to improve immediate pregnancy, as well as long term, outcomes for mother and child.
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| 10. |
- Freitag, C., et al.
(författare)
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Visualizing the entire DNA from a chromosome in a single frame
- 2015
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Ingår i: Biomicrofluidics. - : AIP Publishing. - 1932-1058. ; 9:4
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Tidskriftsartikel (refereegranskat)abstract
- The contiguity and phase of sequence information are intrinsic to obtain complete understanding of the genome and its relationship to phenotype. We report the fabrication and application of a novel nanochannel design that folds megabase lengths of genomic DNA into a systematic back-and-forth meandering path. Such meandering nanochannels enabled us to visualize the complete 5.7 Mbp (1mm) stained DNA length of a Schizosaccharomyces pombe chromosome in a single frame of a CCD. We were able to hold the DNA in situ while implementing partial denaturation to obtain a barcode pattern that we could match to a reference map using the Poland-Scheraga model for DNA melting. The facility to compose such long linear lengths of genomic DNA in one field of view enabled us to directly visualize a repeat motif, count the repeat unit number, and chart its location in the genome by reference to unique barcode motifs found at measurable distances from the repeat. Meandering nanochannel dimensions can easily be tailored to human chromosome scales, which would enable the whole genome to be visualized in seconds. (C) 2015 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.
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