| 371. |
- Persson, Anders, et al.
(författare)
-
Pikeperch Sander lucioperca trapped between niches: foraging performance and prey selection in a piscivore on a planktivore diet
- 2008
-
Ingår i: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 73:4, s. 793-808
-
Tidskriftsartikel (refereegranskat)abstract
- The foraging behaviour of planktivorous pikeperch Sander lucioperca during their first growing season was analysed. Field data showed that S. lucioperca feed on extremely rare prey at the end of the summer, suggesting the presence of a bottleneck. In experiments, foraging ability of planktivorous S. lucioperca was determined when fish were feeding on different prey types (Daphnia magna or Chaoborus spp.) and sizes (1). magna of lengths I or 2.5 turn) when they Occurred alone. Front these results, the minimum density requirement of each prey type was analysed. The energy gain for three different foraging strategies was estimated; a specialized diet based on either large D. magna or Chaoborus spp. or I generalist diet combining both prey types. Prey value estimates showed that Chaoborus Spp. Should be the preferred prey, assuming an energy maximizing principle. In prey choice experiments, S. lucioperca largely followed this principle, including D. magna in the diet only when the density of the Chaoborus spp). was below a threshold value. Splitting the foraging bout into different sequences, however, resulted in a somewhat different pattern. During an initial phase, S. lucioperca captured both prey as encountered and then switched to Chaoborus spp. if prey density wits above (he threshold level. The prey selection observed was mainly explained by sampling behaviour and incomplete information about environmental quality, whereas satiation only had marginal effects. It was concluded that the observed diet based on rare prey items wits in accordance with an optimal foraging strategy and may generate positive growth in the absence of prey fish in suitable sizes. (c) 2008 The Authors Journal compilation (c) 2008 The Fisheries Society of the British Isles.
|
|
| 372. |
|
|
| 373. |
- Persson, Anders, 1953-
(författare)
-
Postmortem Radiology
- 2010
-
Ingår i: First World Congress of Forensic Science.
-
Konferensbidrag (refereegranskat)
|
|
| 374. |
- Persson, Anders, et al.
(författare)
-
Power and resistance, powerlessness and action in school
- 2007
-
Ingår i: Action research. - 9788276347180 ; , s. 203-219
-
Bokkapitel (refereegranskat)abstract
- Action research brings to the fore questions regarding both the power over knowledge building and, consequently, questions on the quality of knowledge. Action research makes visible two dimensions that in this regard are significant. First, the dimension outside-inside where action research more than traditional research voice an inside perspective. This means that those on whom research is conducted receive a greater amount of influence on the problems guiding the research and sometimes become participants in the research process. Secondly, there is the top-bottom dimension, where action research is often associated with a perspective from below. This perspective can, in the hierachies of working life, mean the employees’ perspective, but also the client perspective. In both these dimensions, power and knowledge are intertwined, as it is understood that those people on whom the research is being done get more influence on the research, thereby one must suppose that the quality of knowledge changes. Action research can then not only be close to practice but also to the client. It is also often associated with change, which implies that at times the researcher takes on a more active and intervening role than in traditional research, which at times may mean that established power arrangements are challenged. How then are we to understand action learning, that possibly is something else than action research, within the framework of a power perspective? This is the theme of the ensuing text.
|
|
| 375. |
- Persson, Anders, et al.
(författare)
-
Prisoner resettlement in Sweden
- 2018
-
Ingår i: Prisoner Resettlement in Europe. - 9781138721234 ; , s. 328-342
-
Bokkapitel (refereegranskat)abstract
- In Sweden most prisoners serve a short prison sentence. Since the majority of all prisoners are subject to mandatory pre-release after having served two-thirds of the sentence, few spend more than four months in prison. Still, there is a group who serve prison sentences of two years or more. The resettlement process varies for the two groups, but all prisoners have a right to be supported, aiming for a better life after prison. The Prison and Probation Service (PPS) is one united, state-run organization and both prison and probation staff work together when planning for release and resettlement. There are several resettlement measures, but these are not generally applied as they presuppose an individual assessment. The PPS cooperate with municipalities and the third sector in different arrangements, and the offenders are regarded as a subject in the resettlement process, as they have to agree to any measures taken.
|
|
| 376. |
- Persson, Anders, 1958-, et al.
(författare)
-
Profitable exchanges for scientists: The case of Swedish human embryonic stem cell research
- 2007
-
Ingår i: Health Care Analysis. - : Springer Science and Business Media LLC. - 1065-3058 .- 1573-3394. ; 15, s. 291-304
-
Tidskriftsartikel (refereegranskat)abstract
- In this article two inter-related issues concerning the ongoing commercialisation of biomedical research are analyzed. One aim is to explain how scientists and clinicians at Swedish public institutions can make profits, bot commercially and scientifically, by controlling rare human biological material, like embryos and embryonic stem cell lines. This control in no way presupposes legal ownership or other property rights as initial condition. We show how ethically sensitive material (embryos and stem cell lines) have been used in Sweden as a foundation for a commercial stem cell enterprise-despite all official Swedish strictures agaisnt commercilaisation in this area. We also show how political decisions may amplify the value of controlling this kind of biological material. Another aim of the article is to analyze and discuss the meaning of this kind of academic commercial enterprise in a wider context of research funding strategies. A conclusion that is drawn is that the academic turn to commercial funding sources is dependent on the decline of public funding.
|
|
| 377. |
- Persson, Anders, 1972, et al.
(författare)
-
Programmable Signatures
- 2016
-
Ingår i: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics). - Cham : Springer International Publishing. - 1611-3349 .- 0302-9743. ; 9547, s. 124-135
-
Konferensbidrag (refereegranskat)abstract
- When compiling Embedded Domain Specific Languages (EDSLs) into other languages, the compiler translates types in the source language into corresponding types in the target language. The translation is often driven by a small set of rules that map a single type in the source language into a single type in the target language. This simple approach is limiting when there are multiple possible mappings, and it may lead to poor interoperability and poor performance in the generated code. Instead of hard-wiring a single set of translation rules into a compiler, this paper introduces a small language that lets the programmer describe the mapping of each argument and function separately.
|
|
| 378. |
|
|
| 379. |
- Persson, Anders, et al.
(författare)
-
Radiation tolerance of a spin-dependent tunnelling magnetometer for space applications
- 2011
-
Ingår i: Measurement science and technology. - : IOP Publishing. - 0957-0233 .- 1361-6501. ; 22:4, s. 045204-
-
Tidskriftsartikel (refereegranskat)abstract
- To meet the increasing demand for miniaturized space instruments, efforts have been made to miniaturize traditional magnetometers, e. g. fluxgate and spin-exchange relaxation-free magnetometers. These have, for different reasons, turned out to be difficult. New technologies are needed, and promising in this respect are tunnelling magnetoresistive (TMR) magnetometers, which are based on thin film technology. However, all new space devices first have to be qualified, particularly in terms of radiation resistance. A study on TMR magnetometers' vulnerability to radiation is crucial, considering the fact that they employ a dielectric barrier, which can be susceptible to charge trapping from ionizing radiation. Here, a TMR-based magnetometer, called the spin-dependent tunnelling magnetometer (SDTM), is presented. A magnetometer chip consisting of three Wheatstone bridges, with an angular pitch of 120 degrees, was fabricated using microstructure technology. Each branch of the Wheatstone bridges consists of eight pairs of magnetic tunnel junctions (MTJs) connected in series. Two such chips are used to measure the three-dimensional magnetic field vector. To investigate the SDTM's resistance to radiation, one branch of a Wheatstone bridge was irradiated with gamma rays from a Co-60 source with a dose rate of 10.9 rad min(-1) to a total dose of 100 krad. The TMR of the branch was monitored in situ, and the easy axis TMR loop and low-frequency noise characteristics of a single MTJ were acquired before and after irradiation with the total dose. It was concluded that radiation did not influence the MTJs in any noticeable way in terms of the TMR ratio, coercivity, magnetostatic coupling or low-frequency noise.
|
|
| 380. |
- Persson, Anders, et al.
(författare)
-
Rapid prototyping of magnetic tunnel junctions with focused ion beam processes
- 2010
-
Ingår i: Journal of Micromechanics and Microengineering. - : IOP. - 0960-1317 .- 1361-6439. ; 20:5, s. 055039-
-
Tidskriftsartikel (refereegranskat)abstract
- Submicron sized Magnetic tunnel junctions (MTJs) are most often fabricated by time-consuming and expensive e-beam lithography. From a research and development perspective, a short lead time is one of the major concerns. Here, a rapid process scheme for fabrication of micrometer size MTJs with focused ion beam processes is presented. The magnetic properties of the fabricated junctions is investigated in terms of magnetic domain structure, tunnelling magnetoresistance (TMR) and coercivity, with extra attention to the effect of Ga implantation from the ion beam. In particular, the effect of the implantation on the minimum junction size and the magnetization of the sensing layer are studied. In the latter case, magnetic force microscopy and micromagnetic simulations, with the Object Oriented Micromagnetic Framework (OOMMF), are used to study the magnetization reversal. The fabricated junctions show considerable coercivity both along their hard and easy axes. Interestingly, the sensing layer exhibit two remanent states: one with a single and one with a double domain. The hard axis TMR loop has kinks at about ±20 mT which is attributed to a non-uniform lateral coercivity, where the rim of the junctions, which is subjected to Ga implantation from the flank of the ion beam, is more coercive than the unirradiated centre. The width of the coercive rim is estimated to 160 nm from the hard axis TMR loop. The easy axis TMR loop shows more coercivity than an unirradiated junction and, this too, is found to stem from the coercive rim, as seen from the simulations. It is concluded that the process scheme has three major advantages. Firstly, it has a high lateral and depth resolution – the depth resolution is enhanced by end point detection – and is capable of making junctions of sizes down towards the limit set by the width of the irradiated rim. Secondly, the most delicate process steps are preformed in unbroken vacuum enabling the use of materials prone to forming oxides in the MTJ film stack. Thirdly, the scheme is both uncomplicated and quick and makes it possible to go from design to characterization in the order of hours.
|
|
