| 1. |
- Eklöf-Österberg, Carin, 1987, et al.
(författare)
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Dynamics of Hydride Ions in Metal Hydride-Reduced BaTiO3 Samples Investigated with Quasielastic Neutron Scattering
- 2019
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Ingår i: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 123:4, s. 2019-2030
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Tidskriftsartikel (refereegranskat)abstract
- Perovskite-type oxyhydrides, BaTiO3-xHx, have been recently shown to exhibit hydride-ion (H-) conductivity at elevated temperatures, but the underlying mechanism of hydride-ion conduction and how it depends on temperature and oxygen vacancy concentration remains unclear. Here, we investigate, through the use of quasielastic neutron scattering techniques, the nature of the hydride-ion dynamics in three metal hydride-reduced BaTiO3 samples that are characterized by the simultaneous presence of hydride ions and oxygen vacancies. Measurements of elastic fixed window scans upon heating reveal the presence of quasielastic scattering due to hydride-ion dynamics for temperatures above ca. 200 K. Analyses of quasielastic spectra measured at low (225 and 250 K) and high (400-700 K) temperature show that the dynamics can be adequately described by established models of jump diffusion. At low temperature, <= 250 K, all of the models feature a characteristic jump distance of about 2.8 angstrom, thus of the order of the distance between neighboring oxygen atoms or oxygen vacancies of the perovskite lattice and a mean residence time between successive jumps of the order of 0.1 ns. At higher temperatures, >400 K, the jump distance increases to about 4 angstrom, thus of the order of the distance between next-nearest neighboring oxygen atoms or oxygen vacancies, with a mean residence time of the order of picoseconds. A diffusion constant D was computed from the data measured at low and high temperatures, respectively, and takes on values of about 0.4 X 10(-6) cm(-2) s(-1) at the lowest applied temperature of 225 K and between ca. 20 X 10(-6) and 100 X 10(-6) cm(-2) s(-1) at temperatures between 400 and 700 K. Activation energies E-a were derived from the measurements at high temperatures and take on values of about 0.1 eV and show a slight increase with increasing oxygen vacancy concentration.
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| 2. |
- Frick, Ulrich, et al.
(författare)
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Average volume of alcohol consumption, drinking patterns and related burden of mortality in young people in established market economies in Europe
- 2001
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Ingår i: European Addiction Research. - : S. Karger AG. - 1022-6877 .- 1421-9891. ; 7:3, s. 148-151
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To determine the burden of mortality in young people (age 15-29) in established market economies in Europe in 1999, which is attributable to alcohol consumption. Two dimensions of alcohol consumption were considered: average volume of consumption, and patterns of drinking.METHODS:Mortality data were obtained from the WHO EIP data bank, average volume data from the WHO global databank on alcohol, pattern of drinking data from a questionnaire sent out to experts, from the published literature and from the WHO global databank. Methods are explained and discussed in detail in two other contributions to this volume.RESULTS:More than 8,000 deaths of people aged 15-29 in Europe in 1999 were attributable to alcohol. Young males show a higher proportion of alcohol-attributable deaths (12.8%) than females (8.3%). Both average volume and patterns of drinking contribute to alcohol-related death.CONCLUSIONS:Alcohol-related deaths constitute a considerable burden in young people in Europe.
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| 3. |
- Rehm, Jürgen, et al.
(författare)
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Prevalence of and potential influencing factors for alcohol dependence in Europe
- 2015
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Ingår i: European Addiction Research. - : S. Karger AG. - 1022-6877 .- 1421-9891. ; 21:1, s. 6-18
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Tidskriftsartikel (refereegranskat)abstract
- Alcohol use disorders (AUDs), and alcohol dependence (AD)in particular, are prevalent and associated with a large burdenof disability and mortality. The aim of this study wasto estimate prevalence of AD in the European Union (EU), Iceland, Norway, and Switzerland for the year 2010, and toinvestigate potential influencing factors. The 1-year prevalenceof AD in the EU was estimated at 3.4% among people18–64 years of age in Europe (women 1.7%, men 5.2%), resultingin close to 11 million affected people. Taking into accountall people of all ages, AD, abuse and harmful use resultedin an estimate of 23 million affected people. Prevalenceof AD varied widely between European countries, andwas significantly impacted by drinking cultures and socialnorms. Correlations with level of drinking and other drinking variables and with major known outcomes of heavy drinking,such as liver cirrhosis or injury, were moderate. Theseresults suggest a need to rethink the definition of AUDs.
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| 4. |
- Rehm, Jürgen, et al.
(författare)
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Steps towards constructing a global comparative risk analysis for alcohol consumption: : Determining Indicators and Empirical Weights for Patterns of Drinking, Deciding about Theoretical Minimum, and Dealing with Different Consequences
- 2001
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Ingår i: European Addiction Research. - : S. Karger AG. - 1022-6877 .- 1421-9891. ; 7:3, s. 138-147
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Tidskriftsartikel (refereegranskat)abstract
- In order to conduct a comparative risk analysis for alcohol within the Global Burden of Disease Study (GBD 2000), several questions had to be answered. (1) What are the appropriate dimensions for alcohol consumption and how can they be categorized? The average volume of alcohol and patterns of drinking were selected as dimensions. Both dimensions could be looked upon as continuous but were categorized for practical purposes. The average volume of drinking was categorized into the following categories: abstention; drinking 1 (>0–19.99 g pure alcohol daily for females, >0–39.99 g for males); drinking 2 (20–39.99 g for females, 40–59.99 g for males), and drinking 3 (≥40 g for females, ≥60 g for males). Patterns of drinking were categorized into four levels of detrimental impact based on an optimal scaling analysis of key informant ratings. (2) What is the theoretical minimum for both dimensions? A pattern of regular light drinking (at most 1 drink every day) was selected as theoretical minimum for established market economies for all people above age 45. For all other regions and age groups, the theoretical minimum was set to zero. Potential problems and uncertainties with this selection are discussed. (3) What are the health outcomes for alcohol and how do they relate to the dimensions? Overall, more than 60 disease conditions were identified as being related to alcohol consumption. Most chronic conditions seem to be related to volume only (exceptions are coronary heart disease and ischemic stroke), and most acute conditions seem to be related to volume and patterns. In addition, using methodology based on aggregate data, patterns were relevant for attributing harms for men but not women.
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| 5. |
- Senn, Pascal, et al.
(författare)
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NANOCI-Nanotechnology Based Cochlear Implant With Gapless Interface to Auditory Neurons
- 2017
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Ingår i: Otology and Neurotology. - 1531-7129 .- 1537-4505. ; 38:8, s. E224-E231
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Tidskriftsartikel (refereegranskat)abstract
- Cochlear implants (CI) restore functional hearing in the majority of deaf patients. Despite the tremendous success of these devices, some limitations remain. The bottleneck for optimal electrical stimulation with CI is caused by the anatomical gap between the electrode array and the auditory neurons in the inner ear. As a consequence, current devices are limited through 1) low frequency resolution, hence suboptimal sound quality and 2), large stimulation currents, hence high energy consumption (responsible for significant battery costs and for impeding the development of fully implantable systems). A recently completed, multinational and interdisciplinary project called NANOCI aimed at overcoming current limitations by creating a gapless interface between auditory nerve fibers and the cochlear implant electrode array. This ambitious goal was achieved in vivo by neurotrophin-induced attraction of neurites through an intra-cochlear gel-nanomatrix onto a modified nanoCI electrode array located in the scala tympani of deafened guinea pigs. Functionally, the gapless interface led to lower stimulation thresholds and a larger dynamic range in vivo, and to reduced stimulation energy requirement (up to fivefold) in an in vitro model using auditory neurons cultured on multi-electrode arrays. In conclusion, the NANOCI project yielded proof of concept that a gapless interface between auditory neurons and cochlear implant electrode arrays is feasible. These findings may be of relevance for the development of future CI systems with better sound quality and performance and lower energy consumption. The present overview/review paper summarizes the NANOCI project history and highlights achievements of the individual work packages.
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