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1.	Aartsen, M. G., et al. (author) Multipole analysis of IceCube data to search for dark matter accumulated in the Galactic halo 2015 In: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 75:1 Journal article (peer-reviewed)abstract Dark matter which is bound in the Galactic halo might self-annihilate and produce a flux of stable final state particles, e. g. high energy neutrinos. These neutrinos can be detected with IceCube, a cubic-kilometer sized Cherenkov detector. Given IceCube's large field of view, a characteristic anisotropy of the additional neutrino flux is expected. In this paper we describe a multipole method to search for such a large-scale anisotropy in IceCube data. This method uses the expansion coefficients of a multipole expansion of neutrino arrival directions and incorporates signal-specific weights for each expansion coefficient. We apply the technique to a high-purity muon neutrino sample from the Northern Hemisphere. The final result is compatible with the null-hypothesis. As no signal was observed, we present limits on the self-annihilation cross-section averaged over the relative velocity distribution down to 1.9x10(-23) cm(3) s(-1) for a dark matter particle mass of 700-1,000 GeV and direct annihilation into nu(nu) over bar. The resulting exclusion limits come close to exclusion limits from gamma-ray experiments, that focus on the outer Galactic halo, for high dark matter masses of a few TeV and hard annihilation channels.
2.	Aartsen, M. G., et al. (author) Observation of High-Energy Astrophysical Neutrinos in Three Years of IceCube Data 2014 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 113:10, s. 101101- Journal article (peer-reviewed)abstract A search for high-energy neutrinos interacting within the IceCube detector between 2010 and 2012 provided the first evidence for a high-energy neutrino flux of extraterrestrial origin. Results from an analysis using the same methods with a third year (2012-2013) of data from the complete IceCube detector are consistent with the previously reported astrophysical flux in the 100 TeV-PeV range at the level of 10(-8) GeV cm(-2) s(-1) sr(-1) per flavor and reject a purely atmospheric explanation for the combined three-year data at 5.7 sigma. The data are consistent with expectations for equal fluxes of all three neutrino flavors and with isotropic arrival directions, suggesting either numerous or spatially extended sources. The three-year data set, with a live time of 988 days, contains a total of 37 neutrino candidate events with deposited energies ranging from 30 to 2000 TeV. The 2000-TeV event is the highest-energy neutrino interaction ever observed.
3.	Aartsen, M. G., et al. (author) SEARCHES FOR EXTENDED AND POINT-LIKE NEUTRINO SOURCES WITH FOUR YEARS OF ICECUBE DATA 2014 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 796:2, s. 109- Journal article (peer-reviewed)abstract We present results on searches for point-like sources of neutrinos using four years of IceCube data, including the first year of data from the completed 86 string detector. The total livetime of the combined data set is 1373 days. For an E-2 spectrum, the observed 90% C. L. flux upper limits are similar to 10(-12) TeV-1 cm(-2) s(-1) for energies between 1 TeV and 1 PeV in the northern sky and similar to 10(-11) TeV-1 cm(-2) s(-1) for energies between 100 TeV and 100 PeV in the southern sky. This represents a 40% improvement compared to previous publications, resulting from both the additional year of data and the introduction of improved reconstructions. In addition, we present the first results from an all-sky search for extended sources of neutrinos. We update the results of searches for neutrino emission from stacked catalogs of sources and test five new catalogs; two of Galactic supernova remnants and three of active galactic nuclei. In all cases, the data are compatible with the background-only hypothesis, and upper limits on the flux of muon neutrinos are reported for the sources considered.
4.	Aartsen, M. G., et al. (author) SEARCHES FOR TIME-DEPENDENT NEUTRINO SOURCES WITH ICECUBE DATA FROM 2008 TO 2012 2015 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 807:1 Journal article (peer-reviewed)abstract In this paper searches for flaring astrophysical neutrino sources and sources with periodic emission with the IceCube neutrino telescope are presented. In contrast to time-integrated searches, where steady emission is assumed, the analyses presented here look for a time-dependent signal of neutrinos using the information from the neutrino arrival times to enhance the discovery potential. A search was performed for correlations between neutrino arrival times and directions, as well as neutrino emission following time-dependent light curves, sporadic emission, or periodicities of candidate sources. These include active galactic nuclei, soft gamma-ray repeaters, supernova remnants hosting pulsars, microquasars, and X-ray binaries. The work presented here updates and extends previously published results to a longer period that covers 4 years. of data from 2008 April 5 to 2012 May 16, including the first year of operation of the completed 86 string detector. The analyses did not find any significant time-dependent point sources of neutrinos, and the results were used to set upper limits on the neutrino flux from source candidates.
5.	Aartsen, M. G., et al. (author) Atmospheric and astrophysical neutrinos above 1 TeV interacting in IceCube 2015 In: Physical Review D. - 1550-7998 .- 1550-2368. ; 91:2, s. 022001- Journal article (peer-reviewed)abstract The IceCube Neutrino Observatory was designed primarily to search for high-energy (TeV-PeV) neutLrinos produced in distant astrophysical objects. A search for. greater than or similar to 100 TeV neutrinos interacting inside the instrumented volume has recently provided evidence for an isotropic flux of such neutrinos. At lower energies, IceCube collects large numbers of neutrinos from the weak decays of mesons in cosmic-ray air showers. Here we present the results of a search for neutrino interactions inside IceCube's instrumented volume between 1 TeV and 1 PeV in 641 days of data taken from 2010-2012, lowering the energy threshold for neutrinos from the southern sky below 10 TeV for the first time, far below the threshold of the previous high-energy analysis. Astrophysical neutrinos remain the dominant component in the southern sky down to a deposited energy of 10 TeV. From these data we derive new constraints on the diffuse astrophysical neutrino spectrum, Phi(v) = 2.06(-0.3)(+0.4) x 10(-18) (E-v = 10(5) GeV)-2.46 +/- 0.12GeV-1 cm(-2) sr(-1) s(-1) for 25 TeV < E-v < 1.4 PeV, as well as the strongest upper limit yet on the flux of neutrinos from charmed-meson decay in the atmosphere, 1.52 times the benchmark theoretical prediction used in previous IceCube results at 90% confidence.
6.	Aartsen, M. G., et al. (author) Determining neutrino oscillation parameters from atmospheric muon neutrino disappearance with three years of IceCube DeepCore data 2015 In: Physical Review D. - 1550-7998 .- 1550-2368. ; 91:7 Journal article (peer-reviewed)abstract We present a measurement of neutrino oscillations via atmospheric muon neutrino disappearance with three years of data of the completed IceCube neutrino detector. DeepCore, a region of denser IceCube instrumentation, enables the detection and reconstruction of atmospheric muon neutrinos between 10 and 100 GeV, where a strong disappearance signal is expected. The IceCube detector volume surrounding DeepCore is used as a veto region to suppress the atmospheric muon background. Neutrino events are selected where the detected Cherenkov photons of the secondary particles minimally scatter, and the neutrino energy and arrival direction are reconstructed. Both variables are used to obtain the neutrino oscillation parameters from the data, with the best fit given by Delta m(32)(2) = 2.72(-0.20)(+0.19) x 10(-3) eV(2) and sin(2)theta(23) = 0.53(-0.12)(+0.09) (normal mass ordering assumed). The results are compatible, and comparable in precision, to those of dedicated oscillation experiments.
7.	Aartsen, M. G., et al. (author) Development of a general analysis and unfolding scheme and its application to measure the energy spectrum of atmospheric neutrinos with IceCube 2015 In: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 75:3 Journal article (peer-reviewed)abstract We present the development and application of a generic analysis scheme for the measurement of neutrino spectra with the IceCube detector. This scheme is based on regularized unfolding, preceded by an event selection which uses a Minimum Redundancy Maximum Relevance algorithm to select the relevant variables and a random forest for the classification of events. The analysis has been developed using IceCube data from the 59-string configuration of the detector. 27,771 neutrino candidates were detected in 346 days of livetime. A rejection of 99.9999 % of the atmospheric muon background is achieved. The energy spectrum of the atmospheric neutrino flux is obtained using the TRUEE unfolding program. The unfolded spectrum of atmospheric muon neutrinos covers an energy range from 100 GeV to 1 PeV. Compared to the previous measurement using the detector in the 40-string configuration, the analysis presented here, extends the upper end of the atmospheric neutrino spectrum by more than a factor of two, reaching an energy region that has not been previously accessed by spectral measurements.
8.	Aartsen, M. G., et al. (author) Flavor Ratio of Astrophysical Neutrinos above 35 TeV in IceCube 2015 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 114:17 Journal article (peer-reviewed)abstract A diffuse flux of astrophysical neutrinos above 100 TeV has been observed at the IceCube Neutrino Observatory. Here we extend this analysis to probe the astrophysical flux down to 35 TeV and analyze its flavor composition by classifying events as showers or tracks. Taking advantage of lower atmospheric backgrounds for showerlike events, we obtain a shower-biased sample containing 129 showers and 8 tracks collected in three years from 2010 to 2013. We demonstrate consistency with the (f(e) : f(mu) : f(tau))(circle plus) approximate to (1 : 1 : 1)(circle plus) flavor ratio at Earth commonly expected from the averaged oscillations of neutrinos produced by pion decay in distant astrophysical sources. Limits are placed on nonstandard flavor compositions that cannot be produced by averaged neutrino oscillations but could arise in exotic physics scenarios. A maximally tracklike composition of (0 : 1 : 0)(circle plus) is excluded at 3.3 sigma, and a purely showerlike composition of (1 : 0 : 0)(circle plus) is excluded at 2.3 sigma.
9.	Aartsen, M. G., et al. (author) Search for non-relativistic magnetic monopoles with IceCube 2014 In: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 74:7, s. 2938- Journal article (peer-reviewed)abstract The IceCube Neutrino Observatory is a large Cherenkov detector instrumenting of Antarctic ice. The detector can be used to search for signatures of particle physics beyond the Standard Model. Here, we describe the search for non-relativistic, magnetic monopoles as remnants of the Grand Unified Theory (GUT) era shortly after the Big Bang. Depending on the underlying gauge group these monopoles may catalyze the decay of nucleons via the Rubakov-Callan effect with a cross section suggested to be in the range of to . In IceCube, the Cherenkov light from nucleon decays along the monopole trajectory would produce a characteristic hit pattern. This paper presents the results of an analysis of first data taken from May 2011 until May 2012 with a dedicated slow-particle trigger for DeepCore, a subdetector of IceCube. A second analysis provides better sensitivity for the brightest non-relativistic monopoles using data taken from May 2009 until May 2010. In both analyses no monopole signal was observed. For catalysis cross sections of the flux of non-relativistic GUT monopoles is constrained up to a level of at a 90 % confidence level, which is three orders of magnitude below the Parker bound. The limits assume a dominant decay of the proton into a positron and a neutral pion. These results improve the current best experimental limits by one to two orders of magnitude, for a wide range of assumed speeds and catalysis cross sections.
10.	Aartsen, M. G., et al. (author) Search for Prompt Neutrino Emission from Gamma-Ray Bursts with IceCube 2015 In: Astrophysical Journal Letters. - 2041-8205 .- 2041-8213. ; 805:1 Journal article (peer-reviewed)abstract We present constraints derived from a search of four years of IceCube data for a prompt neutrino flux from gammaray bursts (GRBs). A single low-significance neutrino, compatible with the atmospheric neutrino background, was found in coincidence with one of the 506 observed bursts. Although GRBs have been proposed as candidate sources for ultra-high-energy cosmic rays, our limits on the neutrino flux disfavor much of the parameter space for the latest models. We also find that no more than similar to 1% of the recently observed astrophysical neutrino flux consists of prompt emission from GRBs that are potentially observable by existing satellites.
11.	Aartsen, M. G., et al. (author) Searches for small-scale anisotropies from neutrino point sources with three years of IceCube data 2015 In: Astroparticle physics. - : Elsevier BV. - 0927-6505 .- 1873-2852. ; 66, s. 39-52 Journal article (peer-reviewed)abstract Recently, IceCube found evidence for a diffuse signal of astrophysical neutrinos in an energy range of similar to 60 TeV to the PeV-scale [1]. The origin of those events, being a key to understanding the origin of cosmic rays, is still an unsolved question. So far, analyses have not succeeded to resolve the diffuse signal into point-like sources. Searches including a maximum-likelihood-ratio test, based on the reconstructed directions and energies of the detected down- and up-going neutrino candidates, were also performed on IceCube data leading to the exclusion of bright point sources. In this paper, we present two methods to search for faint neutrino point sources in three years of IceCube data, taken between 2008 and 2011. The first method is an autocorrelation test, applied separately to the northern and southern sky. The second method is a multipole analysis, which expands the measured data in the northern hemisphere into spherical harmonics and uses the resulting expansion coefficients to separate signal from background. With both methods, the results are consistent with the background expectation with a slightly more sparse spatial distribution, corresponding to an underfluctuation. Depending on the assumed number of sources, the resulting upper limit on the flux per source in the northern hemisphere for an E-2 energy spectrum ranges from similar to 1.5. 10(-8) GeV/cm(2) s(-1), in the case of one assumed source, to similar to 4. 10(-10) GeV/cm(2) s(-1), in the case of 3500 assumed sources.
12.	Aartsen, M. G., et al. (author) Search for a diffuse flux of astrophysical muon neutrinos with the IceCube 59-string configuration 2014 In: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:6, s. 062007- Journal article (peer-reviewed)abstract A search for high-energy neutrinos was performed using data collected by the IceCube Neutrino Observatory from May 2009 to May 2010, when the array was running in its 59-string configuration. The data sample was optimized to contain muon neutrino induced events with a background contamination of atmospheric muons of less than 1%. These data, which are dominated by atmospheric neutrinos, are analyzed with a global likelihood fit to search for possible contributions of prompt atmospheric and astrophysical neutrinos, neither of which have yet been identified. Such signals are expected to follow a harder energy spectrum than conventional atmospheric neutrinos. In addition, the zenith angle distribution differs for astrophysical and atmospheric signals. A global fit of the reconstructed energies and directions of observed events is performed, including possible neutrino flux contributions for an astrophysical signal and atmospheric backgrounds as well as systematic uncertainties of the experiment and theoretical predictions. The best fit yields an astrophysical signal flux for nu(mu) + (nu) over bar (mu) of E-2. Phi(E) = 0.25 x 10(-8) GeV cm(-2) s(-1) sr(-1), and a zero prompt component. Although the sensitivity of this analysis for astrophysical neutrinos surpasses the Waxman and Bahcall upper bound, the experimental limit at 90% confidence level is a factor of 1.5 above at a flux of E-2 . Phi(E) = 1.44 x 10(-8) GeV cm(-2) s(-1) sr(-1).
13.	Aartsen, M. G., et al. (author) Search for neutrino-induced particle showers with IceCube-40 2014 In: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:10, s. 102001- Journal article (peer-reviewed)abstract We report on the search for neutrino-induced particle showers, so-called cascades, in the IceCube-40 detector. The data for this search were collected between April 2008 and May 2009 when the first 40 IceCube strings were deployed and operational. Three complementary searches were performed, each optimized for different energy regimes. The analysis with the lowest energy threshold (2 TeV) targeted atmospheric neutrinos. A total of 67 events were found, consistent with the expectation of 41 atmospheric muons and 30 atmospheric neutrino events. The two other analyses targeted a harder, astrophysical neutrino flux. The analysis with an intermediate threshold of 25 TeV leads to the observation of 14 cascadelike events, again consistent with the prediction of 3.0 atmospheric neutrino and 7.7 atmospheric muon events. We hence set an upper limit of E-2 Phi(lim) <= 7.46 x 10(-8) GeV sr(-1) s(-1) cm(-2) (90% C.L.) on the diffuse flux from astrophysical neutrinos of all neutrino flavors, applicable to the energy range 25 TeV to 5 PeV, assuming an E-nu(-2) spectrum and a neutrino flavor ratio of 1: 1: 1 at the Earth. The third analysis utilized a larger and optimized sample of atmospheric muon background simulation, leading to a higher energy threshold of 100 TeV. Three events were found over a background prediction of 0.04 atmospheric muon events and 0.21 events from the flux of conventional and prompt atmospheric neutrinos. Including systematic errors this corresponds to a 2.7 sigma excess with respect to the background-only hypothesis. Our observation of neutrino event candidates above 100 TeV complements IceCube's recently observed evidence for high-energy astrophysical neutrinos.
14.	Aartsen, M. G., et al. (author) SEARCH FOR TIME-INDEPENDENT NEUTRINO EMISSION FROM ASTROPHYSICAL SOURCES WITH 3 yr OF IceCube DATASearch for time-independent neutrino emission from astrophysical sources with 3 yr of icecube data 2013 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 779:2, s. 132- Journal article (peer-reviewed)abstract We present the results of a search for neutrino point sources using the IceCube data collected between 2008 April and 2011 May with three partially completed configurations of the detector: the 40-, 59-, and 79-string configurations. The live-time of this data set is 1040 days. An unbinned maximum likelihood ratio test was used to search for an excess of neutrinos above the atmospheric background at any given direction in the sky. By adding two more years of data with improved event selection and reconstruction techniques, the sensitivity was improved by a factor of 3.5 or more with respect to the previously published results obtained with the 40-string configuration of IceCube. We performed an all-sky survey and a dedicated search using a catalog of a priori selected objects observed by other telescopes. In both searches, the data are compatible with the background-only hypothesis. In the absence of evidence for a signal, we set upper limits on the flux of muon neutrinos. For an E-2 neutrino spectrum, the observed limits are (0.9-5) x 10(-12) TeV-1 cm(-2) s(-1) for energies between 1 TeV and 1 PeV in the northern sky and (0.9-23.2) x 10(-12) TeV-1 cm(-2) s(-1) for energies between 10(2) TeV and 10(2) PeV in the southern sky. We also report upper limits for neutrino emission from groups of sources that were selected according to theoretical models or observational parameters and analyzed with a stacking approach. Some of the limits presented already reach the level necessary to quantitatively test current models of neutrino emission.
15.	Aartsen, M. G., et al. (author) Energy reconstruction methods in the IceCube neutrino telescope 2014 In: Journal of Instrumentation. - 1748-0221. ; 9, s. P03009- Journal article (peer-reviewed)abstract Accurate measurement of neutrino energies is essential to many of the scientific goals of large-volume neutrino telescopes. The fundamental observable in such detectors is the Cherenkov light produced by the transit through a medium of charged particles created in neutrino interactions. The amount of light emitted is proportional to the deposited energy, which is approximately equal to the neutrino energy for v(e) and v(mu) charged-current interactions and can be used to set a lower bound on neutrino energies and to measure neutrino spectra statistically in other channels. Here we describe methods and performance of reconstructing charged-particle energies and topologies from the observed Cherenkov light yield, including techniques to measure the energies of uncontained muon tracks, achieving average uncertainties in electromagnetic-equivalent deposited energy of similar to 15% above 10 TeV.
16.	Aartsen, M. G., et al. (author) Probing the origin of cosmic rays with extremely high energy neutrinos using the IceCube Observatory 2013 In: Physical Review D. - 1550-7998 .- 1550-2368. ; 88:11 Journal article (peer-reviewed)abstract We have searched for extremely high energy neutrinos using data taken with the IceCube detector between May 2010 and May 2012. Two neutrino-induced particle shower events with energies around 1 PeV were observed, as reported previously. In this work, we investigate whether these events could originate from cosmogenic neutrinos produced in the interactions of ultrahigh energy cosmic rays with ambient photons while propagating through intergalactic space. Exploiting IceCube's large exposure for extremely high energy neutrinos and the lack of observed events above 100 PeV, we can rule out the corresponding models at more than 90% confidence level. The model-independent quasidifferential 90% C. L. upper limit, which amounts to E-2 phi(nu e)+(nu mu)+(nu tau) = 1.2 x 10(-7) GeV cm(-2) s(-1) sr(-1) at 1 EeV, provides the most stringent constraint in the energy range from 10 PeV to 10 EeV. Our observation disfavors strong cosmological evolution of the highest energy cosmic-ray sources such as the Fanaroff-Riley type II class of radio galaxies.
17.	Aartsen, M. G., et al. (author) The IceProd framework : Distributed data processing for the IceCube neutrino observatory 2015 In: Journal of Parallel and Distributed Computing. - : Elsevier BV. - 0743-7315 .- 1096-0848. ; 75, s. 198-211 Journal article (peer-reviewed)abstract IceCube is a one-gigaton instrument located at the geographic South Pole, designed to detect cosmic neutrinos, identify the particle nature of dark matter, and study high-energy neutrinos themselves. Simulation of the IceCube detector and processing of data require a significant amount of computational resources. This paper presents the first detailed description of IceProd, a lightweight distributed management system designed to meet these requirements. It is driven by a central database in order to manage mass production of simulations and analysis of data produced by the IceCube detector. IceProd runs as a separate layer on top of other middleware and can take advantage of a variety of computing resources, including grids and batch systems such as CREAM, HTCondor, and PBS. This is accomplished by a set of dedicated daemons that process job submission in a coordinated fashion through the use of middleware plugins that serve to abstract the details of job submission and job management from the framework. (C) 2014 Elsevier Inc. All rights reserved.
18.	Aartsen, M. G., et al. (author) Evidence for High-Energy Extraterrestrial Neutrinos at the IceCube Detector 2013 In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 342:6161, s. 947- Journal article (peer-reviewed)abstract We report on results of an all-sky search for high-energy neutrino events interacting within the IceCube neutrino detector conducted between May 2010 and May 2012. The search follows up on the previous detection of two PeV neutrino events, with improved sensitivity and extended energy coverage down to about 30 TeV. Twenty-six additional events were observed, substantially more than expected from atmospheric backgrounds. Combined, both searches reject a purely atmospheric origin for the 28 events at the 4 sigma level. These 28 events, which include the highest energy neutrinos ever observed, have flavors, directions, and energies inconsistent with those expected from the atmospheric muon and neutrino backgrounds. These properties are, however, consistent with generic predictions for an additional component of extraterrestrial origin.
19.	Aartsen, M. G., et al. (author) First Observation of PeV-Energy Neutrinos with IceCube 2013 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 111:2, s. 021103- Journal article (peer-reviewed)abstract We report on the observation of two neutrino-induced events which have an estimated deposited energy in the IceCube detector of 1.04 +/- 0.16 and 1.14 +/- 0.17 PeV, respectively, the highest neutrino energies observed so far. These events are consistent with fully contained particle showers induced by neutral-current nu(e,mu,tau) ((nu) over bar (e,mu,tau)) or charged-current nu(e) ((nu) over bar (e)) interactions within the IceCube detector. The events were discovered in a search for ultrahigh energy neutrinos using data corresponding to 615.9 days effective live time. The expected number of atmospheric background is 0.082 +/- 0.004(stat)(-0.057)(+0.041)(syst). The probability of observing two or more candidate events under the atmospheric background-only hypothesis is 2.9 x 10(-3) (2.8 sigma) taking into account the uncertainty on the expected number of background events. These two events could be a first indication of an astrophysical neutrino flux; the moderate significance, however, does not permit a definitive conclusion at this time.
20.	Aartsen, M. G., et al. (author) Improvement in fast particle track reconstruction with robust statistics 2014 In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 736, s. 143-149 Journal article (peer-reviewed)abstract The IceCube project has transformed 1 km(3) of deep natural Antarctic ice into a Cherenkov detector Muon neutrinos are detected and their direction is inferred by mapping the light produced by the secondary muon track inside the volume instrumented with photomultipliers. Reconstructing the muon track from the observed light is challenging due to noise, light scattering in the ice medium, and the possibility of simultaneously having multiple muons inside the detector, resulting from the large flux of cosmic ray muons. This paper describes work on two problems: (1) the truck reconstruction problem, in which, given a set of observations, the goal is to recover the track of a muon; and (2) the coincident event problem, which is to determine how many muons are active in the detector during a time window. Rather than solving these problems by developing more complex physical models that are applied at later stages of the analysis, our approach is to augment the detector's early reconstruction with data filters and robust statistical techniques. These can be implemented at the level of on-line reconstruction and, therefore, improve all subsequent reconstructions. Using the metric of median angular resolution, a standard metric for track reconstruction, we improve the accuracy in the initial reconstruction direction by 13%. We also present improvements in measuring the number of muons in coincident events: we can accurately determine the number of muons 98% of the time.
21.	Aartsen, M. G., et al. (author) Measurement of Atmospheric Neutrino Oscillations with IceCube 2013 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 111:8, s. 081801- Journal article (peer-reviewed)abstract We present the first statistically significant detection of neutrino oscillations in the high-energy regime (> 20 GeV) from an analysis of IceCube Neutrino Observatory data collected in 2010 and 2011. This measurement is made possible by the low-energy threshold of the DeepCore detector (similar to 20 GeV) and benefits from the use of the IceCube detector as a veto against cosmic-ray-induced muon background. The oscillation signal was detected within a low-energy muon neutrino sample (20-100 GeV) extracted from data collected by DeepCore. A high-energy muon neutrino sample (100 GeV-10 TeV) was extracted from IceCube data to constrain systematic uncertainties. The disappearance of low-energy upward-going muon neutrinos was observed, and the nonoscillation hypothesis is rejected with more than 5 sigma significance. In a two-neutrino flavor formalism, our data are best described by the atmospheric neutrino oscillation parameters vertical bar Delta m(32)(2)vertical bar = (2.3(-0.5)(+0.6)) x 10(-3) eV(2) and sin(2) (2 theta(23)) > 0.93, and maximum mixing is favored.
22.	Aartsen, M. G., et al. (author) Measurement of the cosmic ray energy spectrum with IceTop-73 2013 In: Physical Review D. - 1550-7998 .- 1550-2368. ; 88:4, s. 042004- Journal article (peer-reviewed)abstract We report on the measurement of the all-particle cosmic ray energy spectrum with the IceTop air shower array in the energy range from 1.58 PeV to 1.26 EeV. The IceTop air shower array is the surface component of the IceCube Neutrino Observatory at the geographical South Pole. The analysis was performed using only information from IceTop. The data used in this work were taken from June 1, 2010 to May 13, 2011. During that period the IceTop array consisted of 73 stations, compared to 81 in its final configuration. The measured spectrum exhibits a clear deviation from a single power law above the knee around 4 PeV and below 1 EeV. We observe spectral hardening around 18 PeV and steepening around 130 PeV.
23.	Aartsen, M. G., et al. (author) Observation of the cosmic-ray shadow of the Moon with IceCube 2014 In: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:10, s. 102004- Journal article (peer-reviewed)abstract We report on the observation of a significant deficit of cosmic rays from the direction of the Moon with the IceCube detector. The study of this "Moon shadow" is used to characterize the angular resolution and absolute pointing capabilities of the detector. The detection is based on data taken in two periods before the completion of the detector: between April 2008 and May 2009, when IceCube operated in a partial configuration with 40 detector strings deployed in the South Pole ice, and between May 2009 and May 2010 when the detector operated with 59 strings. Using two independent analysis methods, the Moon shadow has been observed to high significance (> 6 sigma) in both detector configurations. The observed location of the shadow center is within 0.2 degrees of its expected position when geomagnetic deflection effects are taken into account. This measurement validates the directional reconstruction capabilities of IceCube.
24.	Aartsen, M. G., et al. (author) South Pole glacial climate reconstruction from multi-borehole laser particulate stratigraphy 2013 In: Journal of Glaciology. - 0022-1430 .- 1727-5652. ; 59:218, s. 1117-1128 Journal article (peer-reviewed)abstract The IceCube Neutrino Observatory and its prototype, AMANDA, were built in South Pole ice, using powerful hot-water drills to cleanly bore >100 holes to depths up to 2500 m. The construction of these particle physics detectors provided a unique opportunity to examine the deep ice sheet using a variety of novel techniques. We made high-resolution particulate profiles with a laser dust logger in eight of the boreholes during detector commissioning between 2004 and 2010. The South Pole laser logs are among the most clearly resolved measurements of Antarctic dust strata during the last glacial period and can be used to reconstruct paleoclimate records in exceptional detail. Here we use manual and algorithmic matching to synthesize our South Pole measurements with ice-core and logging data from Dome C, East Antarctica. We derive impurity concentration, precision chronology, annual-layer thickness, local spatial variability, and identify several widespread volcanic ash depositions useful for dating. We also examine the interval around similar to 74 ka recently isolated with radiometric dating to bracket the Toba (Sumatra) supereruption.
25.	Aartsen, M. G., et al. (author) IceCube search for dark matter annihilation in nearby galaxies and galaxy clusters 2013 In: Physical Review D. - 1550-7998 .- 1550-2368. ; 88:12 Journal article (peer-reviewed)abstract We present the results of a first search for self-annihilating dark matter in nearby galaxies and galaxy clusters using a sample of high-energy neutrinos acquired in 339.8 days of live time during 2009/10 with the IceCube neutrino observatory in its 59-string configuration. The targets of interest include the Virgo and Coma galaxy clusters, the Andromeda galaxy, and several dwarf galaxies. We obtain upper limits on the cross section as a function of the weakly interacting massive particle mass between 300 GeV and 100 TeV for the annihilation into b (b) over bar, W+(W) over bar (-), tau(+)tau(-), mu(+)mu(-) , and nu(nu) over bar. A limit derived for the Virgo cluster, when assuming a large effect from subhalos, challenges the weakly interacting massive particle interpretation of a recently observed GeV positron excess in cosmic rays.
26.	Pedersen, TR, et al. (author) Cholesterol lowering and the use of healthcare resources. Results of the Scandinavian Simvastatin Survival Study 1996 In: Circulation. - 0009-7322. ; 93:10, s. 1796-1802 Journal article (peer-reviewed)
27.	Morigny, P, et al. (author) Interaction between hormone-sensitive lipase and ChREBP in fat cells controls insulin sensitivity 2019 In: Nature metabolism. - : Springer Science and Business Media LLC. - 2522-5812. ; 1:1, s. 133-146 Journal article (peer-reviewed)
28.	Ayedh, H. M., et al. (author) Carbon vacancy control in p(+)-n silicon carbide diodes for high voltage bipolar applications 2021 In: Journal of Physics D. - : IOP Publishing. - 0022-3727 .- 1361-6463. ; 54:45 Journal article (peer-reviewed)abstract Controlling the carbon vacancy (V-C) in silicon carbide (SiC) is one of the major remaining bottleneck in manufacturing of high voltage SiC bipolar devices, because V-C provokes recombination levels in the bandgap, offensively reducing the charge carrier lifetime. In literature, prominent V-C evolutions have been measured by capacitance spectroscopy employing Schottky diodes, however the trade-offs occurring in the p(+)-n diodes received much less attention. In the present work, applying similar methodology, we showed that V-C is re-generated to its unacceptably high equilibrium level at similar to 2 x10(13) V-C cm(-3) by 1800 degrees C anneals required for the implanted acceptor activation in the p(+)-n components. Nevertheless, we have also demonstrated that the V-C eliminating by thermodynamic equilibrium anneals at 1500 degrees C employing carbon-cap can be readily integrated into the p(+)-n components fabrication resulting in <= 10(11) V-C cm(-3), potentially paving the way towards the realization of the high voltage SiC bipolar devices.
29.	Hallén Sandgren, C, et al. (author) Homogeneity density scores of quarter milk in automatic milking systems. 2021 In: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 104:9, s. 10121-10130 Journal article (peer-reviewed)abstract Milk quality and clinical mastitis in dairy cows are monitored by detecting visually abnormal milk. A standardized method to evaluate clots in milk and studies of the incidence and dynamics of clots in milk at the quarter level are lacking. We validated a method to score clot density in quarter milk samples and describe the prevalence and dynamics of the density scores between consecutive samplings and periods in 4 farms with automatic milking systems. Using in-line filters, we collected quarter milk samples at each milking during 3 periods of 30 h each in each farm. Clot density was scored based on coverage of the filter area as 0 (negative), 1 (trace), 2 (mild), 3 (moderate), 4 (heavy), and 5 (very heavy). The score for a specific quarter and milking is referred to as the quarter milking score (QMS). Three assessors independently scored 902 images of filter samples with a Fleiss kappa value of 0.72. In total, 21,202 quarter milk samples from 5,398 milkings of 621 cows were collected. Of the quarter filter samples, 2.4% had visible clots, distributed as mild (1.4%), moderate (0.6%), heavy (0.3%), and very heavy (<0.1%, n = 8). Cases with a cow period sum of QMS ≥ 4, corresponding to 9.4% of all periods, harbored 86% and 94% of all QMS of 2 to 5 and 3 to 5, respectively. Of these cases, cows sampled in all 3 periods and clots in only 1 period had a quarter period sum score ≥ 1 in 1.8 different quarters in average. Corresponding numbers for the cows with clots or traces in 2 or 3 periods were 2.2 and 2.5 different quarters, respectively. A QMS of 2 to 5 in the preceding milking increased the chance of a QMS >1 in the following milking, with an average chance of 38%. The probability of a QMS > 1 increased with increasing previous QMS, a higher sum of QMS during the milking period, longer milking interval, and higher lactation number, but decreased with increasing days in milk. Our study showed that the method of clot-density scoring is feasible to perform and reproducible for investigating the occurrence and dynamics of clots in milk. Elevated clot-density scores clustered within certain cows and cow periods and appeared in new quarters of the cows over time. The low recurrence of QMS of 1 and 2 within quarters indicated that QMS 3 could be a reasonable threshold for detecting quarters with abnormal milk that require further attention.
30.	Agell, J, et al. (author) Översyn av ekonomprogrammet vid Uppsala universitet : Slutrapport avlämnad den 20 maj 1998 från en arbetsgrupp tillsatt av Samhällsvetenskapliga fakultetsnämnden den 24 april 1997 1998 Reports (other academic/artistic)
31.	Andersson, Agnes, et al. (author) Headache Before and After Endoscopic Transsphenoidal Pituitary Tumor Surgery: A Prospective Study 2022 In: Journal of Neurological Surgery Part B-Skull Base. - : Georg Thieme Verlag KG. - 2193-6331 .- 2193-634X. ; 83:suppl. 2 Journal article (peer-reviewed)abstract Objective Headache is a common symptom among patients with pituitary tumors, as it is in the general population. The aim of the study was to investigate headache as a symptom in patients with pituitary tumors before and 6 months after endoscopic transsphenoidal surgery (TSS). Design This is a prospective observational cohort study. Setting This study was conducted at university tertiary referral hospital. Participants A total of 110 adult patients underwent endoscopic TSS for pituitary tumors. Main Outcome Measures The Migraine Disability Assessment (MIDAS) questionnaire was used before and 6 months after surgery for the assessment of headache. Clinical variables with potential influence on headache were analyzed. Results Sixty-eight (62%) patients experienced headaches at least once during the 3 months before surgery. Thirty (27%) patients reported disabling headache before surgery, with younger age being an independent associated factor ( p <0.001). In patients with disabling headache before surgery, the median (interquartile range) MIDAS score improved from 78 (27-168) to 16 (2-145; p =0.049), headache frequency decreased from 45 (20-81) to 14 (4-35) days ( p =0.009), and headache intensity decreased from 6 (5-8) to 5 (4-7) ( p =0.011) after surgery. In total, 16 of the 30 (53%) patients reported a clinically relevant improvement and five (17%) a clinically relevant worsening. Four (5%) patients developed new disabling headache. No predictor for postoperative improvement of headache was identified. Conclusion In this prospective study, the results show that disabling headache improves following endoscopic TSS in a subset of patients with pituitary tumors. However, no predictive factors for improvement could be identified.
32.	Andersson, Christer, et al. (author) Manifest för lämplig styrning av hälso- och sjukvården 2018 In: Läkartidningen. - 0023-7205. ; 115:3 Journal article (peer-reviewed)
33.	Anglart, D., et al. (author) Comparison of methods for predicting cow composite somatic cell counts 2020 In: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 103:9, s. 8433-8442 Journal article (peer-reviewed)
34.	Anglart, D, et al. (author) Detecting and predicting changes in milk homogeneity using data from automatic milking systems. 2021 In: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 104:10, s. 11009-11017 Journal article (peer-reviewed)abstract To ensure milk quality and detect cows with signs of mastitis, visual inspection of milk by prestripping quarters before milking is recommended in many countries. An objective method to find milk changed in homogeneity (i.e., with clots) is to use commercially available inline filters to inspect the milk. Due to the required manual labor, this method is not applicable in automatic milking systems (AMS). We investigated the possibility of detecting and predicting changes in milk homogeneity using data generated by AMS. In total, 21,335 quarter-level milk inspections were performed on 5,424 milkings of 624 unique cows on 4 farms by applying visual inspection of inline filters that assembled clots from the separate quarters during milking. Images of the filters with clots were scored for density, resulting in 892 observations with signs of clots for analysis (77% traces or mild cases, 15% moderate cases, and 8% heavy cases). The quarter density scores were combined into 1 score indicating the presence of clots during a single cow milking and into 2 scores summarizing the density scores in cow milkings during a 30-h sampling period. Data generated from the AMS, such as milk yield, milk flow, conductivity, and online somatic cell counts, were used as input to 4 multilayer perceptron models to detect or predict single milkings with clots and to detect milking periods with clots. All models resulted in high specificity (98-100%), showing that the models correctly classified cow milkings or cow milking periods with no clots observed. The ability to successfully classify cow milkings or cow periods with observed clots had a low sensitivity. The highest sensitivity (26%) was obtained by the model that detected clots in a single milking. The prevalence of clots in the data was low (2.4%), which was reflected in the results. The positive predictive value depends on the prevalence and was relatively high, with the highest positive predictive value (72%) reached in the model that detected clots during the 30-h sampling periods. The misclassification rate for cow milkings that included higher-density scores was lower, indicating that the models that detected or predicted clots in a single milking could better distinguish the heavier cases of clots. Using data from AMS to detect and predict changes in milk homogeneity seems to be possible, although the prediction performance for the definitions of clots used in this study was poor.
35.	Azarov, A., et al. (author) Effects of annealing on photoluminescence and defect interplay in ZnO bombarded by heavy ions : Crucial role of the ion dose 2020 In: Journal of Applied Physics. - : American Institute of Physics (AIP). - 0021-8979 .- 1089-7550. ; 127:2 Journal article (peer-reviewed)abstract Bombardment of ZnO with heavy ions generating dense collision cascades is of particular interest because of the formation of nontrivial damage distribution involving a defected layer located between the surface and the bulk damage regions, as seen by Rutherford backscattering spectroscopy in the channeling mode. By correlating photoluminescence and channeling data, we demonstrate that the thermal evolution of defects in wurtzite ZnO single crystals implanted with Cd ions strongly depends on the implanted dose. Specifically, the ion dose has a profound effect on the optical response in the spectral range between the near-band-edge emission and deep-level emission bands. The interplay between interstitial and vacancy type defects during annealing is discussed in relation to the evolution of the multipeak damage distribution.
36.	Brynne, N, et al. (author) Fluoxetine inhibits the metabolism of tolterodine-pharmacokinetic implications and proposed clinical relevance 1999 In: British journal of clinical pharmacology. - : Wiley. - 0306-5251. ; 48:4, s. 553-563 Journal article (peer-reviewed)
37.	Brynne, N, et al. (author) Ketoconazole inhibits the metabolism of tolterodine in subjects with deficient CYP2D6 activity 1999 In: British journal of clinical pharmacology. - : Wiley. - 0306-5251. ; 48:4, s. 564-572 Journal article (peer-reviewed)
38.	Carlsson, Eva, 1959, et al. (author) The Prevalence of Ostomy-related Complications 1 Year after Ostomy Surgery: A Prospective, Descriptive, Clinical Study 2016 In: Ostomy/Wound Management. - 0889-5899. ; 62:10, s. 34-48 Journal article (peer-reviewed)abstract Despite advancements in the creation and care of stomas, ostomy and peristomal skin complications are common immediately following surgery as well as in the months and years thereafter. A prospective study to determine the prevalence of ostomy and peristomal skin complications and the influence of ostomy configuration on such complications was conducted 1 year after ostomy surgery among all patients at a university hospital in Sweden. All participants received regular (10 to 14 days post discharge, 6 weeks, 3 months, 6 months, and 1 year post surgery) ostomy follow-up care by a wound ostomy continence (WOC) nurse. All consecutive elective and emergency patients who had undergone surgery to create a colostomy (end colostomy), end ileostomy, or loop ileostomy were eligible to participate. Patients who were reoperated during their first year post-surgery, patients with a urostomy, and patients with double ostomies were excluded from the study. Patient data collected included age, gender, diagnosis, elective or emergency surgery, open or laparoscopic surgical procedure, presence of a colorectal surgeon specialist at surgery, type of ostomy (colostomy, end ileostomy, loop ileostomy), preoperative ostomy siting, counseling, body mass index, American Society of Anesthesiologists classification, and radiation and/or chemotherapy status. Ostomies were evaluated by 4 WOC nurses as to stoma configuration, convexity use, patient self-sufficiency in stoma care, and complications. All 207 patients (53% women) who were eligible agreed to participate in the study. Patient median age was 70 years (range 19-94); 74% underwent elective surgery. Main diagnoses were colorectal cancer (62%) and inflammatory bowel disease (19%). Ostomy types were: colostomy (71%), end ileostomy (26%), and loop ileostomy (3%). One or more complications occurred in 35% of the patients (27% ostomy complications, 11% peristomal skin complications). A colostomy hernia was the most common surgical complication (20%), and significantly more women (69%) and emergency surgeries were noted among patients with a colostomy and an ostomy height of ≤5 mm. The use of convexity was significantly more common among patients with a stoma height of ≤5 mm than patients with stomas >5 mm (P ≤ 0.016) and among patients having emergency operations than among patients having elective surgery (P ≤ 0.045). Of the emergency surgeries, 37% had not been ostomy-sited (P <0.0001). With regular WOC nurse follow-up, the prevalence of peristomal skin complications in this population was low, and adequate ostomy height might have prevented the frequent use of convexity. Explorative studies are needed that consider differences in body configuration when determining optimal stoma height, especially for patients who require emergency surgery.
39.	Covacu, Ruxandra, et al. (author) Nitric oxide exposure diverts neural stem cell fate from neurogenesis towards astrogliogenesis 2006 In: Stem Cells. - : Oxford University Press (OUP). - 1066-5099 .- 1549-4918. ; 178, s. 268-268 Journal article (other academic/artistic)abstract Regeneration of cells in the central nervous system is a process that might be affected during neurological disease and trauma. Because nitric oxide (NO) and its derivatives are powerful mediators in the inflammatory cascade, we have investigated the effects of pathophysiological concentrations of NO on neurogenesis, gliogenesis, and the expression of proneural genes in primary adult neural stem cell cultures. After exposure to NO, neurogenesis was downregulated, and this corresponded to decreased expression of the proneural gene neurogenin-2 and beta-III-tubulin. The decreased ability to generate neurons was also found to be transmitted to the progeny of the cells. NO exposure was instead beneficial for astroglial differentiation, which was confirmed by increased activation of the Janus tyrosine kinase/signal transducer and activator of transcription transduction pathway. Our findings reveal a new role for NO during neuroinflammatory conditions, whereby its proastroglial fate-determining effect on neural stem cells might directly influence the neuroregenerative process.
40.	David, M. L., et al. (author) Electrically active defects in irradiated 4H-SiC 2004 In: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 95:9, s. 4728-4733 Journal article (peer-reviewed)abstract 4H-SiC epilayers were irradiated with either protons or electrons and electrically active defects were studied by means of deep level transient spectroscopy. Motion of defects has been found to occur at temperature as low as 350-400 K. Indeed, the application of an electric field has been found to enhance modifications in defect concentrations that can also occur during long time annealing at elevated temperature. Two levels have been revealed and labeled B and M. Two other levels, referred to as S-1 and S-2 and located at 0.40 and 0.71 eV below the conduction band edge have been studied in detail (capture cross sections, profiling, formation energy, activation energy during annealing). The S-1 and S-2 levels have been found to exhibit a one to one relation and are proposed to be two charge states of the same acceptor center, labeled the S center.
41.	Domeika, Marius, et al. (author) Guidelines for the laboratory diagnosis of Chlamydia trachomatis infections in East European countries 2009 In: Journal of the European Academy of Dermatology and Venereology. - : Wiley. - 0926-9959 .- 1468-3083. ; 23:12, s. 1353-1363 Research review (peer-reviewed)abstract The present guidelines aim to provide comprehensive information regarding the laboratory diagnosis of infections caused by Chlamydia trachomatis in East European countries. These recommendations contain important information for laboratory staff working with sexually transmitted infections (STIs) and/or STI-related issues. Individual East European countries may be required to make minor national adjustments to these guidelines as a result of lack of accessibility to some reagents or equipment, or laws in a specific country.
42.	Domeika, Marius, et al. (author) Guidelines for the laboratory diagnosis of genital herpes in eastern European countries 2010 In: Eurosurveillance. - 1560-7917. ; 15:44, s. 21-27 Journal article (peer-reviewed)abstract These guidelines aim to provide comprehensive information about sexually transmitted herpes simplex virus (HSV) infection and its laboratory diagnosis in eastern European countries. They are primarily intended for professionals testing specimens from patients at a sexual healthcare clinic but may also be helpful for community-based screening programmes. In particular, the guidelines recommend: (i) either viral culture or validated and approved nucleic acid amplification tests (NAATs) as the tests of choice for symptomatic patients, which should be promoted for laboratory confirmation of HSV infection; (ii) if culture or NAATs are not available, antigen detection - a direct immunofluorescence test or enzyme immunoassay from samples from symptomatic patients - could be employed, but HSV type determination is of importance; (iii) only type-specific serology should be used for detecting asymptomatic individuals, testing pregnant women at risk of acquiring HSV infection close to delivery, men who have sex with men and people who are HIV positive; (iv) widespread screening for HSV antibodies should be discouraged; and (v) any non-validated diagnostic tests should be validated against a recommended, approved gold standard.
43.	Domeika, Marius, et al. (author) Guidelines for the laboratory diagnosis of trichomoniasis in East European countries 2010 In: Journal of the European Academy of Dermatology and Venereology. - : Wiley. - 0926-9959 .- 1468-3083. ; 24:10, s. 1125-1134 Research review (peer-reviewed)abstract The laboratory diagnosis of sexually transmitted infections in many Eastern European countries remains suboptimal. The main objective of the present evidence-based guidelines is to provide comprehensive information regarding the laboratory diagnosis of infections caused by Trichomonas vaginalis in East European countries. In particular, the present guidelines recommend: (i) to encourage examination of the wet mounts of vaginal exudates, instead of stained smears, at all clinical settings; (ii) nucleic acid amplification tests (NAATs) or culture could be employed if no trichomonads are detected on microscopic examination of the wet preparation and there is a strong indication of infection and (iii) the use of NAATs is encouraged in screening, using non-invasive specimens, or high volume testing situations. In the absence of internationally recognized commercial NAAT systems, tests developed in-house should be validated using obtainable international standards and quality assured strictly. Individual East European countries may be required to make minor national adjustments to these guidelines as a result of lack of accessibility to some reagents or equipment, or laws in a specific country.
44.	Edmondson, P. D., et al. (author) Helium bubble distributions in a nanostructured ferritic alloy 2013 In: Journal of Nuclear Materials. - : Elsevier BV. - 0022-3115 .- 1873-4820. ; 434:1-3, s. 210-216 Journal article (peer-reviewed)abstract A 14YWT nanostructured ferritic alloy (NFA) was implanted with He + ions to fluences of 6.75 × 1021 He m-2 at 400 °C in order to simulate the effects of high He concentrations produced in advanced fission and future fusion reactors at an accelerated timescale. The He bubble size distributions associated with specific microstructural features were characterized by a combination of transmission electron microscopy and atom probe tomography. Helium bubbles were observed on grain boundaries, dislocations, and on the surfaces of nanoclusters and larger Ti(N,C) precipitates. A polydisperse distribution of bubble sizes was observed in the ferrite matrix. With the exception of He bubbles on dislocations, bubbles were observed to increase in size with increasing fluence. The combined TEM and APT data indicates that ∼4.4% of the bubbles are located on coarse precipitates, ∼12.2% at dislocations, ∼14.4% at grain boundaries, and ∼48.6% on nanoclusters, and the remainder as isolated bubbles in the ferrite matrix. The abundances of these different trapping sites, especially the nanoclusters, might reduce the availability and mobility of He, and possibly the susceptibility of these alloys to He embrittlement.
45.	Edmondson, P. D., et al. (author) Helium entrapment in a nanostructured ferritic alloy 2011 In: Scripta Materialia. - : Elsevier BV. - 1359-6462 .- 1872-8456. ; 65:8, s. 731-734 Journal article (peer-reviewed)abstract A nanostructured ferritic alloy was irradiated with He+ to simulate service in a nuclear reactor and to test the hypothesis that the surface of nanoclusters is a preferential nucleation site for He bubbles. Transmission electron microscopy and atom probe tomography showed direct evidence of He bubble nucleation on the surfaces of nanoclusters and Ti(N,C) precipitates, and along grain boundaries and dislocations, thereby demonstrating an alloy design approach to improve the radiation tolerance of structural steels in the extreme environments found in nuclear reactors.
46.	Fingren, J., et al. (author) A Prospective, Explorative Study to Assess Adjustmen 1 Year After Ostomy Surgery Among Swedish Patients 2018 In: Ostomy Wound Management. - : HMP Communications, LLC. - 0889-5899 .- 1943-2720. ; 64:6, s. 12-22 Journal article (peer-reviewed)abstract Having ostomy surgery changes a person's life. To assess adjustment to life with an ostomy and quality of life (QOL) 1 year after ostomy surgery, a prospective, explorative study was conducted among patients of a stoma clinic at a university hospital in Sweden.All consecutive patients who had undergone nonemergent or emergency surgery involving formation of an ostomy and who received regular follow-up at the ward and at the outpatient clinic during the first year by an enterostomal therapist (ET) were prospectively included in the study; their demographic information (including age, gender, diagnosis/reason for an ostomy, nonemergent or emergency surgery, ostomy type, preoperative counselling/siting [Yes/No], self-sufficiency in stoma care, professional activity, and whether they lived with a spouse/partner) was recorded upon admission to the study. Participants independently completed the Ostomy Adjustment Scale (OAS), a 36-item instrument, with each response scored from worst to best adjustment (1 to 6) for a total score ranging from 36-216. The tool addresses 5 factors: normal functioning, functional limitations, negative affect, positive role function, and positive affect. In addition, QOL was assessed using a visual analogue scale (0 to 100 mm) along with 2 open-ended QOL questions. Quantitative and qualitative data were included on the same questionnaire and were entered into an Excel file by 2 of the researchers. The quantitative data were transferred to statistical software for analysis; the qualitative data were analyzed according to Graneheim and Lundman. Descriptive statistics were used for quantitative data and based on nonparametric analysis, and qualitative data were analyzed using content analysis. Of the 150 patients eligible for inclusion (82 women, 68 men, median age 70 [range 21-90] years), 110 (73%) underwent nonemergent surgery, 106 (71%) had a colostomy, and 44 (29%) had an ileostomy. Most ostomies were created due to cancer (98, 65%) and inflammatory bowel disease (28, 19%), and 90% of participants were self-sufficient in ostomy care. The overall median score on the OAS was 162 with no significant differences between genders and diagnoses. The OAS scores for patients who did versus did not have preoperative counselling by an ET were 163 and 150, respectively (P = .313). Mean OAS scores were 136 for patients with cancer and an ileostomy and 163 for patients with cancer and a colostomy. Patients with cancer and an ileostomy had a significantly worse adjustment (mean 3.6 +/- 1.32) than patients with cancer and a colostomy (mean 4.4 +/- 1.21) in the factor Normal (P = .015). Lowest adjustment scores were in the areas of sexual activities and attractiveness and participating in sports and physical activities; the highest scores concerned contact with an ET, feeling well informed, and knowing the correct methods of handling the ostomy. The median score for QOL for all patients was 76 (interquartile range 59-86). Three (3) categories emerged from the qualitative content analysis as obstacles to QOL: ostomy-related concerns and impact on life, limitations in physical and social activities, and negative impact on physical and mental health. The ET was found to have an important role in education and counselling to promote adjustment to life with an ostomy from preoperative to follow-up care. Future explorative studies are needed to determine how patients want questions about sex and sensitive issues to be designed and how the ET can best discuss sexuality and intimacy after ostomy surgery.
47.	Gustafsson, Oscar, et al. (author) Long-wavelength infrared quantum-dot based interband photodetectors 2011 In: Infrared physics & technology. - : Elsevier BV. - 1350-4495 .- 1879-0275. ; 54:3, s. 287-291 Journal article (peer-reviewed)abstract We report on the design and fabrication of (Al)GaAs(Sb)/InAs tensile strained quantum-dot (QD) based detector material for thermal infrared imaging applications in the long-wavelength infrared (LWIR) regime. The detection is based on transitions between confined dot states and continuum states in a type-II band lineup, and we therefore refer to it as a dot-to-bulk (D2B) infrared photodetector with expected benefits including long carrier lifetime due to the type-II band alignment, suppressed Shockley-Read-Hall generation-recombination due to the relatively large-bandgap matrix material, inhibited Auger recombination processes due to the tensile strain and epitaxial simplicity. Metal-organic vapor-phase epitaxy was used to grow multiple (Al)GaAs(Sb) QD layers on InAs substrates at different QD nominal thicknesses, compositions, doping conditions and multilayer periods, and the material was characterized using atomic force and transmission electron microscopy, and Fourier-transform infrared absorption spectroscopy. Dot densities up to 1 x 10(11) cm(-2), 1 x 10(12) cm(-2) and 3 x 10(10) cm(-2) were measured for GaAs, AlGaAs and GaAsSb QDs, respectively. Strong absorption in GaAs, AlGaAs and GaAsSb multilayer QD samples was observed in the wavelength range 6-12 mu m. From the wavelength shift in the spectral absorption for samples with varying QD thickness and composition it is believed that the absorption is due to an intra- valance band transition. From this it is possible to estimate the type-II inter-band transition wavelength, thereby suggesting that (Al)GaAs(Sb) QD/InAs heterostructures are suitable candidates for LWIR detection and imaging.
48.	Gustafsson, O, et al. (author) Long-wavelength infrared quantum-dot based interbphotodetectors 2010 In: Infrared physics & technology. - 1350-4495 .- 1879-0275. ; 54:3, s. 287- Journal article (peer-reviewed)
49.	Hallen, H, et al. (author) Variations in congestion of the nasal mucosa in man 1996 In: Clinical otolaryngology and allied sciences. - : Wiley. - 0307-7772 .- 1365-2273. ; 21:5, s. 396-399 Journal article (peer-reviewed)
50.	Hallen, K, et al. (author) Modulation of neuronal nitric oxide release by soluble guanylyl cyclase in guinea pig colon 2001 In: Biochemical and biophysical research communications. - : Elsevier BV. - 0006-291X. ; 280:4, s. 1130-1134 Journal article (peer-reviewed)

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