| 1. |
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| 2. |
- Elamalayil Soman, Deepak, et al.
(author)
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Discontinuous conduction mode of a three-level boost DC-DC converter and its merits and limits for voltage cross regulation applications
- 2014
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In: Proceedings, IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society. - : IEEE conference proceedings. - 9781479940325 ; , s. 4268-4272
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Conference paper (peer-reviewed)abstract
- Distributed generation and smart grid integration of renewable energy sources introduce a lot of challenges for the enabling power electronic converter technology. Some of these challenges include wide controllability range, high power handling and good reliability. Three-level boost converter is one of the attractive solution for applications requiring voltage cross regulation such as three-level neutral point clamped inverter based grid integration of renewable sources. The present work shows the advantages and disadvantages of using discontinuous conduction mode of a Three-level boost converter for voltage cross regulation. The converter working principle, modes of operation and operating cases are listed briefly. The simulation results compare the DCM and CCM cross regulation effects. Based on these results, the controllability range of the converter is analyzed to understand the suitability of the converter for various applications.
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| 6. |
- Ouacha, Aziz, et al.
(author)
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Wideband multibeam antenna for integration in small platforms in EuCAP 2010 - The 4th European Conference on Antennas and Propagation, vol , issue , pp 5505825
- 2010
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In: EuCAP 2010 - The 4th European Conference on Antennas and Propagation.
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Conference paper (peer-reviewed)abstract
- A wideband multibeam antenna for integration in small platforms such as UAVs has been demonstrated. The demonstration was performed on a single facet comprising an 8×4 bowtie antenna elements array and a beamforming network which includes both transmitter and receiver chains and can therefore be used in multifunction systems for EW and communication. The operating frequency band chosen for this demonstrator is 6 - 15 GHz. Due to the modularity of the concept, the demonstrated facet can either be used stand alone or forming a faceted array depending on the required field of coverage and/or platform structure. A compact and lightweight phased array concept for 360o coverage is also discussed.
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| 7. |
- Samuelsson, S, et al.
(author)
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Phonological and surface profiles of reading difficulties among very low birth weight children : Converging evidence for the developmental lag hypothesis.
- 2000
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In: Scientific Studies of Reading. - 1088-8438 .- 1532-799X. ; 4:3, s. 197-217
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Journal article (peer-reviewed)abstract
- The purpose of this study was to test the developmental lag hypothesis, which assumes that a surface pattern of reading difficulties should be attributed to a general developmental delay rather than to specific deficits in the acquisition of orthographic decoding skills. We compared a sample of very low birth weight children (less than 1,500 g), known to be at higher risk of a general developmental delay, with a group of same-age, normal readers. Following the same regression-based procedures seen in the work of Castles and Coltheart (1993); Manis, Seidenberg, Doi, McBride-Chang, and Petersen (1996); and Stanovich, Siegel, and Gottardo (1997), we found that only 1 very low birth weight child could be classified as phonologically dyslexic, whereas 12 out of 60 very low birth weight children were identified as surface dyslexic. This subgroup of children with surface dyslexia was impaired not only in all reading measures employed in this study, but also in several behavioral domains associated with a developmental lag.
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| 8. |
- Smeds, K., et al.
(author)
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Objective measures to quantify the perceptual effects of noise reduction in hearing aids
- 2011
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In: Proceedings of the AES International Conference. ; , s. 101-108
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Conference paper (peer-reviewed)abstract
- Twenty listeners with hearing impairment evaluated three noise-reduction algorithms using paired comparisons of speech clarity, noise loudness, and preference. The subjective test produces results in terms of physical signal-to-noise ratios that correspond to equal subjective performance with and without the noise-reduction algorithms. This facilitates a direct test of how well a number of objective performance measures correspond with the subjective test results.
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| 12. |
- Andersson, M. G., et al.
(author)
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Separated by a common language : Awareness of term usage differences between languages and disciplines in biopreparedness
- 2013
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In: Biosecurity and bioterrorism. - : Mary Ann Liebert Inc. - 1538-7135 .- 1557-850X. ; 11:SUPPL. 1, s. S276-S285
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Journal article (peer-reviewed)abstract
- Preparedness for bioterrorism is based on communication between people in organizations who are educated and trained in several disciplines, including law enforcement, health, and science. Various backgrounds, cultures, and vocabularies generate difficulties in understanding and interpretating terms and concepts, which may impair communication. This is especially true in emergency situations, in which the need for clarity and consistency is vital. The EU project AniBioThreat initiated methods and made a rough estimate of the terms and concepts that are crucial for an incident, and a pilot database with key terms and definitions has been constructed. Analysis of collected terms and sources has shown that many of the participating organizations use various international standards in their area of expertise. The same term often represents different concepts in the standards from different sectors, or, alternatively, different terms were used to represent the same or similar concepts. The use of conflicting terminology can be problematic for decision makers and communicators in planning and prevention or when handling an incident. Since the CBRN area has roots in multiple disciplines, each with its own evolving terminology, it may not be realistic to achieve unequivocal communication through a standardized vocabulary and joint definitions for words from common language. We suggest that a communication strategy should include awareness of alternative definitions and ontologies and the ability to talk and write without relying on the implicit knowledge underlying specialized jargon. Consequently, cross-disciplinary communication skills should be part of training of personnel in the CBRN field. In addition, a searchable repository of terms and definitions from relevant organizations and authorities would be a valuable addition to existing glossaries for improving awareness concerning bioterrorism prevention planning. © 2013, Mary Ann Liebert, Inc.
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| 13. |
- Barsoe, S, et al.
(author)
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RT-qPCR assay for detection of mink astrovirus in outbreaks of diarrhea on Danish mink farms
- 2021
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In: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 16:5, s. e0252022-
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Journal article (peer-reviewed)abstract
- Diarrhea in mink kits is a major cause of disease and mortality in the mink production. The etiology remains unknown in most outbreaks due to a lack of diagnostic assays. In the current study we present an RT-qPCR method to detect mink astrovirus in fecal samples from mink kits with diarrhea. All sampled animals were classified based on age and patoanatomical evaluation as having pre-weaning diarrhea, diarrhea in the growth period or as having no macroscopic signs of diarrhea. Fecal samples were analyzed for MiAstV with RT-qPCR, next generation sequencing and electron microscopy in parallel. Mink astrovirus was detected with RT-qPCR in 92 out of 203 samples. This detection was confirmed by next generation sequencing in a high proportion of samples (22/27), and by visualization of astrovirus particles with EM in some of the samples. Mink astrovirus was highly prevalent (68%) among kits in the outbreaks of pre-weaning diarrhea, in particular outbreaks from May, while less prevalent in outbreaks in June. Mink astrovirus was detected in outbreaks of diarrhea in the growth period, though in a much lesser extent than in the pre-weaning period. The role of mink astrovirus in the diarrhea disease complex of mink remain to be investigated, and for that purpose this sensitive and robust RT-qPCR can be a valuable tool in the future.
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| 17. |
- Carpman, Nicole
(author)
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Resource characterization and variability studies for marine current power
- 2017
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Doctoral thesis (other academic/artistic)abstract
- Producing electricity from marine renewable resources is a research area that develops continuously. The field of tidal energy is on the edge to progress from the prototype stage to the commercial stage. However, tidal resource characterization, and the effect of tidal turbines on the flow, is still an ongoing research area in which this thesis aims to contribute.In this thesis, measurements of flow velocities have been performed at three kinds of sites. Firstly, a tidal site has been investigated for its resource potential in a fjord in Norway. Measurements have been performed with an acoustic Doppler current profiler to map the spatial and temporal characteristics of the flow. Results show that currents are in the order of 2 m/s in the center of the channel. Furthermore, the flow is highly bi-directional between ebb and flood flows. The site thus has potential for in-stream energy conversion. Secondly, a river site serves as an experimental site for a marine current energy converter that has been designed at Uppsala University and deployed in Dalälven, Söderfors. The flow rate at the site is regulated by an upstream hydro power plant, making the site suitable for experiments on the performance of the vertical axis turbine in a natural environment. The turbine was run in steady discharge flows and measurements were performed to characterize the extent of the wake. Lastly, at an ocean current site, the effect that transiting ferries may have on submerged devices was investigated. Measurements were conducted with two sonar systems to obtain an underwater view of the wake caused by a propeller and a water jet thruster respectively.Furthermore, the variability of the intermittent renewable sources wind, solar, wave and tidal energy was investigated for the Nordic countries. All of the sources have distinctly different variability features, which is advantageous when combining power generated from them and introducing it on the electricity grid. Tidal variability is mainly due to four aspects: the tidal regime, the tidal cycle, local bathymetry causing turbulence, asymmetries etc. and weather effects. Models of power output from the four sources was set up and combined in different energy mixes for a “highly renewable” and a “fully renewable” scenario. By separating the resulting power time series into different frequency bands (long-, mid-, mid/short-, and short-term components) it was possible to minimize the variability on different time scales. It was concluded that a wise combination of intermittent renewable sources may lower the variability on short and long time scales, but increase the variability on mid and mid/short time scales.The tidal power variability in Norway was then investigated separately. The predictability of tidal currents has great advantages when planning electricity availability from tidal farms. However, the continuously varying tide from maximum power output to minimum output several times per day increases the demand for backup power or storage. The phase shift between tidal sites introduces a smoothing effect on hourly basis but the tidal cycle, with spring and neap tide simultaneously in large areas, will inevitably affect the power availability.
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| 18. |
- Dahlquist, M., et al.
(author)
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Methodology for quantifying perceptual effects from noise suppression systems
- 2005
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In: International Journal of Audiology. - : Informa UK Limited. - 1499-2027 .- 1708-8186. ; 44:12, s. 721-732
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Journal article (peer-reviewed)abstract
- Methodology is proposed for perceptual assessment of both subjective sound quality and speech recognition in such way that results can be compared between these two aspects, Validation is performed with a noise suppression system applied to hearing instruments. A method termed Interpolated Paired Comparison Rating (IPCR) was developed for time efficient assessment of subjective impression of different aspects of sound quality for a variety of noise conditions. The method is based on paired comparisons between processed and unprocessed stimuli, and the results are expressed as the difference in signal-to-noise ratio (dB) between these that give equal subjective impression. For tests of speech recognition in noise, validated adaptive test methods can be used that give results in terms of speech-to-noise ratio. The methodology was shown to be sensitive enough to detect significant mean differences between processed and unprocessed speech in noise, both regarding subjective sound quality and speech recognition ability in groups consisting of 30 subjects. An effect on sound quality from the noise suppression equivalent to about 3-4 dB is required to be statistically significant for a single subject. A corresponding effect of 3-6 dB is required for speech recognition (one-sided test). The magnitude of difference that occurred in the present study for sound quality was sufficient to show significant differences for sound quality within individuals, but this was not the case for speech recognition.
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| 19. |
- Felix, Richard A, et al.
(author)
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Sound rhythms are encoded by postinhibitory rebound spiking in the superior paraolivary nucleus
- 2011
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In: Journal of Neuroscience. - 0270-6474 .- 1529-2401. ; 31:35, s. 12566-12578
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Journal article (peer-reviewed)abstract
- The superior paraolivary nucleus (SPON) is a prominent structure in the auditory brainstem. In contrast to the principal superior olivary nuclei with identified roles in processing binaural sound localization cues, the role of the SPON in hearing is not well understood. A combined in vitro and in vivo approach was used to investigate the cellular properties of SPON neurons in the mouse. Patch-clamp recordings in brain slices revealed that brief and well timed postinhibitory rebound spiking, generated by the interaction of two subthreshold-activated ion currents, is a hallmark of SPON neurons. The I(h) current determines the timing of the rebound, whereas the T-type Ca(2+) current boosts the rebound to spike threshold. This precisely timed rebound spiking provides a physiological explanation for the sensitivity of SPON neurons to sinusoidally amplitude-modulated (SAM) tones in vivo, where peaks in the sound envelope drive inhibitory inputs and SPON neurons fire action potentials during the waveform troughs. Consistent with this notion, SPON neurons display intrinsic tuning to frequency-modulated sinusoidal currents (1-15Hz) in vitro and discharge with strong synchrony to SAMs with modulation frequencies between 1 and 20 Hz in vivo. The results of this study suggest that the SPON is particularly well suited to encode rhythmic sound patterns. Such temporal periodicity information is likely important for detection of communication cues, such as the acoustic envelopes of animal vocalizations and speech signals.
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| 20. |
- Finnström, Orvar, 1938-, et al.
(author)
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Very-low-birth-weight children at school age : Academic achievement, behavior and self-esteem and relation to risk factors
- 2003
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In: The Journal of Maternal-Fetal & Neonatal Medicine. - 1476-7058 .- 1476-4954. ; 14:2, s. 75-84
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Journal article (peer-reviewed)abstract
- Objective: To investigate school performance, behavior and self-esteem of children with very low birth weight (VLBW). Methods: All children with birth weight below 1501 g (VLBW) and normal birth weight controls, born in the south-east region of Sweden during a 15-month period in 1987-88, were enrolled in a prospective follow-up study. At the age of 9 years, 81% and 82%, respectively, were re-examined regarding growth, neurofunctional classification, academic achievement tests, need for special education and behavioral problems. At 12 years, 89% and 76%, respectively, were re-examined regarding growth, neurofunctional classification, visual acuity and self-esteem. Results: VLBW children were shorter and lighter, and differed from the controls with regard to neurological functional classification. They produced poorer results in most academic achievement tests. When the comparison was restricted to children with normal intelligence, almost all the differences in other academic achievements disappeared. VLBW children had more reading difficulties but were less often than expected defined as dyslexics compared to control children. We did not find any major disparity in visual acuity and self-esteem between the groups. Low Apgar scores, intracranial hemorrhage and the need for mechanical ventilation neonatally were associated with poorer results in most outcome measures. Neurofunctional assessments in early childhood were associated with most outcome measures. The mother's education was related to delayed reading skills and need for special education. Conclusions: Although VLBW children performed less well in most academic achievement tests and on some behavioral subscales, those who had a normal intellectual capacity did not differ in any important aspects from the controls.
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| 21. |
- Hensing, Gunnel, 1956, et al.
(author)
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Experienced dilemmas of everyday life in chronic neuropathic pain patients--results from a critical incident study.
- 2007
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In: Scandinavian journal of caring sciences. - : Wiley. - 0283-9318 .- 1471-6712. ; 21:2, s. 147-54
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Journal article (peer-reviewed)abstract
- Neuropathic pain is a disabling chronic condition with limited therapeutic options. Few studies have addressed patient's experience and strategies. The aim of this study was to explore dilemmas experienced in order to improve care and rehabilitation. An interview study with 39 patients suffering from neuropathic pain of different origin was performed. We used the critical incident technique to collect data. Questions on occasions when patients had been hindered by or reminded of their neuropathic pain were included, and the self-perceived consequences and management of such occasions. The interviews were transcribed verbatim and analysed qualitatively. A broad range of experiences categorised into dilemmas, disturbances, consequences and managements from most parts of everyday life was identified. The dilemmas were 'housework', 'sitting', 'physical activity', 'personal hygiene', 'sleeping difficulties', 'hypersensitivity to external stimuli', 'social relationships', 'transportation' and 'leisure time'. Disturbances were 'failures', 'inabilities' and 'restrictions'. Consequences were 'increased pain', 'psychological reactions' and 'physical symptoms'. The majority of the patients used activity-oriented strategies to manage their pain such as alternative ways of performing the task, a cognitive approach or simply ignoring the pain. This is one of the first studies presenting detailed data on everyday dilemmas, disturbances and consequences of patients with chronic neuropathic pain. Such information is important in clinical settings to improve care and rehabilitation.
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| 22. |
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| 23. |
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| 24. |
- Leijon, Arne, et al.
(author)
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Analysis of data from the International Outcome Inventory for Hearing Aids (IOI-HA) using Bayesian Item Response Theory
- 2020
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In: International Journal of Audiology. - : Taylor & Francis. - 1499-2027 .- 1708-8186.
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Journal article (peer-reviewed)abstract
- Objective: IOI-HA response data are conventionally analysed assuming that the ordinal responses have interval-scale properties. This study critically considers this assumption and compares the conventional approach with a method using Item Response Theory (IRT). Design: A Bayesian IRT analysis model was implemented and applied to several IOI-HA data sets. Study sample: Anonymised IOI-HA responses from 13273 adult users of one or two hearing aids in 11 data sets using the Australian English, Dutch, German and Swedish versions of the IOI-HA. Results: The raw ordinal responses to IOI-HA items do not represent values on interval scales. Using the conventional rating sum as an overall score introduces a scale error corresponding to about 10 − 15% of the true standard deviation in the population. Some interesting and statistically credible differences were demonstrated among the included data sets. Conclusions: It is questionable to apply conventional statistical measures like mean, variance, t-tests, etc., on the raw IOI-HA ratings. It is recommended to apply only nonparametric statistical test methods for comparisons of IOI-HA results between groups. The scale error can sometimes cause incorrect conclusions when individual results are compared. The IRT approach is recommended for analysis of individual results.
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| 25. |
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| 26. |
- Leijon, M., et al.
(author)
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STRUCTURAL CHARACTERIZATION OF PNA-DNA DUPLEXES BY NMR - EVIDENCE FOR DNA IN A B-LIKE CONFORMATION
- 1994
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In: Biochemistry. - : American Chemical Society (ACS). - 1520-4995 .- 0006-2960. ; 33:33, s. 9820-9825
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Journal article (peer-reviewed)abstract
- The nucleic acid analogues PNA (peptide nucleic acids) hybridize with DNA of complementary sequence. The solution structures of two PNA-DNA duplexes, H-(GCTATGTC)-NH2.d(GACATAGC) and H-(GTAGATCACT)-NH2.d(AGTGATCTAC), have been studied by H-1 NMR. It was found that the PNA-DNA hybrids are base paired by hydrogen bonds, most likely of the Watson-Crick type. From two-dimensional NOESY and COSY results it is concluded that the DNA strand in the PNA-DNA complex adopts a B-like structure with the deoxyribose sugars in the C2'-endo conformation.
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| 27. |
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| 28. |
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| 29. |
- Lindblom, Adam, et al.
(author)
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High-voltage pulsed-power cable generator
- 2009
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In: IEEE Transactions on Plasma Science. - USA : IEEE. - 0093-3813 .- 1939-9375. ; 37:1, s. 236-242
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Journal article (peer-reviewed)abstract
- A cable-based 25-GW pulsed-power generator with output impedance of 2 is presented. It is designed to deliver a 200-ns-long 500-kV pulse into a 10 load. The primary energy storage of the generator consists of a 50-kV 20-kJ capacitor bank. The 50-kV capacitor bank is discharged into a 1 : 12 transformer. The transformer is designed to charge a pulse-forming line (PFL) to 600 kV. When charged, the PFL is discharged into a load via a spark gap. The spark gap is located in a coaxial system containing deionized water together with the cable endings of the PFL and transformer. The electric field at the cable endings is refractively graded by the high permittivity of the surrounding water. The primary and secondary windings consist of high-voltage cables that are interleaved and wound together. The PFL consists of eight 40-m-long 110-kV coaxial cables with both ends connected to the load. Each cable screen is grounded in the middle and connected in parallel. The cables have a characteristic impedance of 30 . The parallel cable setup gives the PFL an impedance of 2 . The total length, height, and width of the pulse generator are 4, 2, and 1.2 m, respectively.
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| 30. |
- Lundin, Staffan
(author)
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Marine Current Energy Conversion
- 2016
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Doctoral thesis (other academic/artistic)abstract
- Marine currents, i.e. water currents in oceans and rivers, constitute a large renewable energy resource. This thesis presents research done on the subject of marine current energy conversion in a broad sense.A review of the tidal energy resource in Norway is presented, with the conclusion that tidal currents ought to be an interesting option for Norway in terms of renewable energy.The design of marine current energy conversion devices is studied. It is argued that turbine and generator cannot be seen as separate entities but must be designed and optimised as a unit for a given conversion site. The influence of support structure for the turbine blades on the efficiency of the turbine is studied, leading to the conclusion that it may be better to optimise a turbine for a lower flow speed than the maximum speed at the site.The construction and development of a marine current energy experimental station in the River Dalälven at Söderfors is reported. Measurements of the turbine's power coefficient indicate that it is possible to build efficient turbines for low flow speeds. Experiments at the site are used for investigations into different load control methods and for validation of a numerical model of the energy conversion system and the model's ability to predict system behaviour in response to step changes in operational tip speed ratio.A method for wake measurements is evaluated and found to be useful within certain limits. Simple models for turbine runaway behaviour are derived, of which one is shown by comparison with experimental results to predict the behaviour well.
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| 31. |
- Neumann, Hartmut P., et al.
(author)
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65 YEARS OF THE DOUBLE HELIX Genetics informs precision practice in the diagnosis and management of pheochromocytoma
- 2018
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In: Endocrine-Related Cancer. - : BIOSCIENTIFICA LTD. - 1351-0088 .- 1479-6821. ; 25:8, s. T201-T219
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Research review (peer-reviewed)abstract
- Although the authors of the present review have contributed to genetic discoveries in the field of pheochromocytoma research, we can legitimately ask whether these advances have led to improvements in the diagnosis and management of patients with pheochromocytoma. The answer to this question is an emphatic Yes! In the field of molecular genetics, the well-established axiom that familial (genetic) pheochromocytoma represents 10% of all cases has been overturned, with amp;gt;35% of cases now attributable to germline disease-causing mutations. Furthermore, genetic pheochromocytoma can now be grouped into five different clinical presentation types in the context of the ten known susceptibility genes for pheochromocytoma-associated syndromes. We now have the tools to diagnose patients with genetic pheochromocytoma, identify germline mutation carriers and to offer gene-informed medical management including enhanced surveillance and prevention. Clinically, we now treat an entire family of tumors of the paraganglia, with the exact phenotype varying by specific gene. In terms of detection and classification, simultaneous advances in biochemical detection and imaging localization have taken place, and the histopathology of the paraganglioma tumor family has been revised by immunohistochemical-genetic classification by gene-specific antibody immunohistochemistry. Treatment options have also been substantially enriched by the application of minimally invasive and adrenal-sparing surgery. Finally and most importantly, it is now widely recognized that patients with genetic pheochromocytoma/paraganglioma syndromes should be treated in specialized centers dedicated to the diagnosis, treatment and surveillance of this rare neoplasm.
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| 35. |
- Svahn, MG, et al.
(author)
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Adding functional entities to plasmids
- 2004
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In: The journal of gene medicine. - : Wiley. - 1099-498X .- 1521-2254. ; 66 Suppl 1, s. S36-S44
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Journal article (peer-reviewed)
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