| 1. |
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| 2. |
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| 3. |
- Johansson, Mikael, et al.
(författare)
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Memory for perceived and imagined pictures : an event-related potential study
- 2002
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Ingår i: Neuropsychologia, vol. 40, no. 7. - : Elsevier. ; 40:7, s. 986-1002
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Konferensbidrag (refereegranskat)abstract
- Event-related potentials (ERPs) and behavioural measures were used to investigate recognition memory and source-monitoring judgements about previously perceived and imagined pictures. At study, word labels of common objects were presented. Half of these were followed by a corresponding picture and the other half by an empty frame, signalling to the participants to mentally visualise an image. At test, participants in a source-monitoring task made a three-way discrimination between new words and words corresponding to previously perceived and imagined pictures. Participants in an old/new-recognition task indicated whether test words were previously presented or not. In both tasks, correctly identified old items elicited more positive-going ERPs than correctly judged new items. This widely distributed old/new effect was found to have an earlier onset and to be of a greater magnitude for imagined than for perceived items. Task (source versus item-memory) affected the old/new effects over prefrontal areas and the reaction times to remembered old items. The present findings are consistent with the view that a greater amount, or a different type, of information is necessary for accurate source-memory judgements than for correct recognition, and moreover, that different types of source-specifying information revive at different rates. In addition, the results add weight to the view that the late widespread ERP-old/new effect is sensitive to the quality or the amount of information retrieved from memory.
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| 4. |
- Tiihonen, Mikael, et al.
(författare)
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A UV laser source for biological and chemical sensing
- 2004
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Ingår i: FREE-SPACE LASER COMMUNICATION AND ACTIVE LASER ILLUMINATION III. - BELLINGHAM : SPIE-INT SOC OPTICAL ENGINEERING. - 0819450332 ; , s. 127-136, s. 127-
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Konferensbidrag (refereegranskat)abstract
- Optical parametric oscillator (OPO) and sum-frequency mixing (SFM) devices are useful tools for constructing ultraviolet (UV) laser sources for fluorescence spectroscopy. Here, a compact UV-laser sources based on frequency conversion of an actively Q-switched Nd:YAG laser is presented. The second harmonic generation from a Nd:YAG laser was utilized as pump radiation for a periodically poled KTiOPO4 nanosecond optical parametric oscillator(1). The OPO-signal and the remaining pump were spatially mode-matched for Type I SFM in a beta-barium borate (BBO) crystal and UV radiation at 293 nm could be generated. This corresponds to a conversion efficiency of 2% with respect to the 532 nm harmonic radiation. The wavelength region accessible with this UV source is useful for chemical and biological sensing. Excitation of tryptophan at 293 nm for detection of fluorescence emission in ovalbumin and transthyretin was demonstrated.
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| 5. |
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| 6. |
- Andersson, Åke, et al.
(författare)
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Status of the new injector for MAX-lab
- 2002
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Ingår i: 8th European Particle Accelerator Conference. ; , s. 772-774
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Konferensbidrag (refereegranskat)abstract
- The new injector for MAX-lab is built around two 125 MeV linacs [B. Anderberg, (2000)] equipped with SLED cavities [Z.D. Farkas, (1974)]. The electron beam is recirculated once to reach 500 MeV. A 2.3 MeV thermionic RF gun [B. Anderberg, (2000)] injects into the system. The RF-gun is put into operation and commissioning of the first linac is proceeding. Results from the thermionic RF-gun operation, linac commissioning and first beam operations are presented.
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| 7. |
- Carlsson, Richard, et al.
(författare)
-
Core Erlang 1.0 language specification
- 2000
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- We describe a core language for the concurrent functional language Erlang, aptly named “Core Erlang”, presenting its grammar and informal static and dynamic semantics relative to Erlang. We also discuss built-in functions and other open issues, and sketch a syntax tree representation.
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| 8. |
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| 9. |
- Eriksson, Mikael, et al.
(författare)
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A cascaded optical klystron on an energy recovery linac - race track microtron
- 2003
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 507:1-2, s. 470-474
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Tidskriftsartikel (refereegranskat)abstract
- We are currently investigating a device capable of generating continuous, coherent radiation down in the Angstrom region in sub-ps pulses in a relatively compact set-up. By placing a cascaded optical klystron (OK) in the return path of a 3 GeV Race Track Microtron operating in Energy Recovery mode Harmonic Generation can be performed in several stages in parallel. A four stage OK can generate Angstrom radiation from a 266 nm seed. The demands on the electron optics are severe, but the requirements on the electron beam are not extreme. The layout of a possible facility is presented and the basic concepts are discussed below. (C) 2003 Elsevier Science B.V. All rights reserved.
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| 10. |
- Eriksson, Mikael, et al.
(författare)
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MAX4, a 3 GeV light source with a flexible injector
- 2002
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Ingår i: 8th European Particle Accelerator Conference. ; , s. 686-687
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Konferensbidrag (refereegranskat)abstract
- The MAX4 ring is intended to be the future user facility at MAXlab. The high-brilliance 3 GeV storage ring, equipped with small gap, short period superconducting undulators, demonstrates a high mean brilliance over a wide photon energy spectrum. The ring itself is defined from the routine operation of the small gap insertion devices, which is reflected in the small aperture of the ring magnets. The development of future light sources, like the free electron laser and energy recovery systems, opens up new challenging possibilities to create high brilliance, short pulse radiation. This development is today far from being mature, a strong development of new ideas and techniques will most probably take place during the next decade(s). The MAX4 full-energy injector is constructed to incorporate these future developments. The proposed 3 GeV energy recovery race-track microtron will open up the possibility of topping up injection and to deliver Fourier transform limited spontaneous as well as coherent radiation up to the hard X-ray spectral region
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| 11. |
- Eriksson, Mikael, et al.
(författare)
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The magnet lattice of the MAX IV storage rings
- 2004
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Ingår i: AIP Conference Proceedings. - : AIP. - 0094-243X .- 1551-7616. ; 705, s. 157-160
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Konferensbidrag (refereegranskat)abstract
- A successor of the present MAX facility is currently being studied. This proposed MAX IV facility will then have two new storage rings operated at 1.5 and 3 GeV respectively. The magnet lattices of the two storage rings are almost identical and the rings are placed coaxially, one on top of the other. A third ring, the MAX III ring, now under construction, should be transferred to the new facility. These three rings will then offer dipole IR radiation and undulator radiation from 5 eV up to 20 keV. The total number of straight sections is 32, of which 28 could be used for insertion devices. A 3 GeV linear accelerator will be used as injector for the three rings. The linac could also be used as a free electron laser source. The magnet lattice of the two new rings is described below. The electron beam emittance of the 3 GeV storage ring is 0.86 nm rad and 0.3 nm rad for the 1.5 GeV ring. The circumference of the rings is 286 m
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| 12. |
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| 13. |
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| 14. |
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| 15. |
- Hällstig, Emil, 1975-
(författare)
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Nematic Liquid Crystal Spatial Light Modulators for Laser Beam Steering
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Laser beam control is important in many applications. Phase modulating spatial light modulators (SLMs) can be used to electronically alter the phase distribution of an optical wave-front and thus change the direction and shape of a laser beam. Physical constraints set limitations to the SLM and an ideal phase distribution can usually not be realised. In order to understand how such components can be used for non-mechanical beam control three nematic liquid crystal (NLC) SLMs have been thoroughly characterised and modelled.The pixel structure and phase quantisation give a discrepancy between ideal and realised phase distributions. The impact on beam steering capability was examined by measurements and simulations of the intensity distribution in the far-field.In two of the studied SLMs the pixel period was shorter than the thickness of the LC layer giving the optical phase shift. This results in a so-called “fringing field”, which was shown to degrade the phase modulation and couple light between polarisation modes. The deformation of the LC was simulated and a finite-difference time-domain (FDTD) algorithm was used to calculate how polarised light propagates through the optically anisotropic SLM.Non-mechanical beam steering and tracking in an optical free-space communication link were demonstrated. Continual optimisation of the steering angle was achieved by feedback from a video camera.The optical properties of the SLM in the time period right after a voltage update were studied. It was shown how light is redistributed between orders during the switching from one blazed grating to another. By appropriate choice of the blazed gratings the effects on the diffraction efficiency can be minimised.The detailed knowledge of the SLM structure and its response to electronic control makes it possible to predict and optimise the device performance in future systems.
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| 16. |
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| 17. |
- Johansson, Mikael, et al.
(författare)
-
Memory for perceived and imagined pictures: An event-related potential study
- 2002
-
Ingår i: Neuropsychologia. - 1873-3514. ; 40:7, s. 986-1002
-
Tidskriftsartikel (refereegranskat)abstract
- Event-related potentials (ERPs) and behavioral measures were used to investigate recognition memory and source-monitoring judgements about previously perceived and imagined pictures. At study, word labels of common objects were presented. Half of these were followed by a corresponding picture and the other half by an empty frame, signalling to the Ss (aged 20-35 yrs) to mentally visualize an image. At test, Ss in a source-monitoring task made a 3-way discrimination between new words and words corresponding to previously perceived and imagined pictures. Ss in an old/new-recognition task indicated whether test words were previously presented or not. In both tasks, correctly identified old items elicited more positive-going ERPs than correctly judged new items. This widely distributed old/new effect was found to have an earlier onset and to be of a greater magnitude for imagined than for perceived items. Task affected the old/new effects over prefrontal areas and the reaction times to remembered old items. Findings are consistent with the view that a greater amount, or a different type, of information is necessary for accurate source-memory judgements than for correct recognition, and moreover, that different types of source-specifying information revive at different rates.
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| 18. |
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| 19. |
- Jonas, Örtegren, et al.
(författare)
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Cone motion viscosity and optical second harmonic generation of ferroelectric liquid crystalline dendrimers
- 2001
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Ingår i: Liquid crystals (Print). - : Informa UK Limited. - 0267-8292 .- 1366-5855. ; 28:6, s. 861-868
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Tidskriftsartikel (refereegranskat)abstract
- We report second harmonic generation in a ferroelectric liquid crystalline trimer and ferroelectric liquid crystalline dendrimers of first, second and third generation. Thin cells were filled with the compounds by capillary forces at elevated temperature, and cooled from the surface stabilized ferroelectric state to below the glass transition temperature, while kept in an electric field. The cone motion viscosity and the threshold electric field for unwinding of the helix axis of the chiral tilted smectic mesophases were studied separately at elevated temperature, and these data were used to optimize the preparation of the films. The measured response time was between 0.3 and 3 ms, which corresponds to a cone motion viscosity between 0.5 and 50 Pa s. Second harmonic generation was studied both at elevated temperature with an electric field and at room temperature with and without electric field. The first generation dendrimer exhibited a strong increase in the second order non-linear optical response with time at room temperature. The d(23)-coefficient of this dendrimer was approximately four times larger than for the other macromolecules and was 0.045 pm V-1. The relatively large d-coefficient of the first generation dendrimer is ascribed to crystallization, which improved the orientation of the molecular dipoles.
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| 20. |
- Kerttu, Mikael, et al.
(författare)
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Switching activity estimation of finite state machines for low power synthesis
- 2002
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Ingår i: Proceedings. - Piscataway, NJ : IEEE Communications Society. - 0780374487 ; , s. 65-68
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Konferensbidrag (refereegranskat)abstract
- A technique for computing the switching activity of synchronous finite state machine (FSM) implementations including the influence of temporal correlation among the next state signals is described. The approach is based upon the computation that a FSM is in a given state which, in turn, is used to compute the conditional probability that a next state bit changes given its present state value. All computations are performed using decision diagram (DD) data structures. As an application of this method, the next state activity information is utilized for low power optimization in the synthesis of binary decision diagram (BDD) mapped circuits. Experimental results are presented based on a set of the ISCAS89 sequential benchmarks showing an average power reduction of 40 percent and tip to 90 percent reduction for individual benchmarks on the estimated power dissipation.
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| 21. |
- LeBlanc, Gregory, et al.
(författare)
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MAX 4, A 3 GEV light source
- 2003
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Ingår i: Proceedings of the IEEE Particle Accelerator Conference. ; 4, s. 2321-2323
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Konferensbidrag (refereegranskat)abstract
- A proposal for a new synchrotron light source, MAX 4, is presented. The main components are two identical storage rings operated at different electron beam energies and equipped with superconducting insertion devices. Small beam emittances will yield high brilliance radiation over a wide spectral range. A small horizontal emittance is achieved by using a large number of cells with gradient dipoles flanked by horizontally focusing quadrupoles. A small magnet aperture allows strong gradients in dipoles and strong sextupole components in quadrupoles. This results in an equilibrium emittance on the order of 1 nmrad. A full-energy injector, enabling top-up operation, will be a 3 GeV S-band linac with an energy doubling system. This opens up the possibility to produce short, intense radiation pulses, coherent as well as spontaneous.
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| 22. |
- LeBlanc, Gregory, et al.
(författare)
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Status of the MAX III storage ring
- 2003
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Ingår i: Particle Accelerator Conference 2003, Stanford, USA.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 23. |
- Lindgren, A. C., et al.
(författare)
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Characterization of strained Si/Si1-xGex/Si heterostructures annealed in oxygen or argon
- 2002
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 91:5, s. 2708-2712
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Tidskriftsartikel (refereegranskat)abstract
- The strained Si/Si1-xGex/Si layer heterostructure heat treated from 700 degreesC to 950 degreesC in Ar (annealing) or O-2-C2H2Cl2 (oxidation) was characterized using high-resolution x-ray diffraction in combination with Rutherford backscattering. Only small changes to the structure are observed up to 800 degreesC, within the resolution limits of diffraction and backscattering. Severe strain relaxation occurs at 950 degreesC and the heterostructure tends to relax more during annealing in Ar than during oxidation in O-2-C2H2Cl2. The strain relaxation is mainly caused by interdiffusion of Si and Ge rather than formation of misfit dislocations. Diffusion of Si interstitials generated during oxidation into the heterostructure is suggested as the cause responsible for the less pronounced interdiffusion of Si and Ge in the oxidized samples.
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| 24. |
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| 25. |
- Lindgren, Johan, et al.
(författare)
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The first record of the mosasaur Clidastes from Europe and its palaeogeographical implications
- 2004
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Ingår i: Acta Palaeontologica Polonica. - 0567-7920. ; 49:2, s. 219-234
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Tidskriftsartikel (refereegranskat)abstract
- Remains of the mosasaur Clidastespropython in marine strata of latest early Campanian age from the Kristianstad Basin, southern Sweden, represent the first record of Clidastes outside of North America. The material consists of shed marginal and pterygoid tooth-crowns, and vertebrae (including eleven associated cervicals and dorsals from a juvenile). The majority of the teeth and skeletal elements can be referred to juveniles (mostly in the estimated 2-3 m total body length range), but large, presumably adult individuals (up to an estimated total length of 6 in) are also represented. Available data indicate that the Kristianstad Basin population of C. propython represents a short-lived migration, most likely from the Mississippi Embayment in North America. The local extinction of Clidastes in southern Sweden, tentatively placed at the early/late Campanian boundary (sensu germanico), may coincide with that in the Western Interior Seaway and Gulf Coast of North America. Within the Kristianstad Basin area, Clidastes occurs in high-energy, shallow water deposits, where it is the most common mosasaur. This finding is in stark contrast to recent publications suggesting that Clidastes inhabited mainly off-shore, deeper waters.
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| 26. |
- Lindgren, Johan, et al.
(författare)
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Tylosaurus ivoensis: a giant mosasaur from the early Campanian of Sweden
- 2002
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Ingår i: Transactions of the Royal Society of Edinburgh. Earth Sciences. - 0263-5933. ; 93, s. 73-93
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Forskningsöversikt (refereegranskat)abstract
- The nominal species Mosasaurus ivoensis from the latest early Campanian of the Kristianstad Basin in southern Sweden, is redescribed and assigned to the tylosaurine genus Tylosaurus on the basis of its dental and vertebral morphology. A partial skeleton (KUVP 1024) from the late Coniacian to earliest Campanian Smoky Hill Chalk Member of the Niobrara Formation in western Kansas, USA, was previously referred to 'M'. ivoensis. Nevertheless, its marginal teeth are markedly different, both in size and morphology, from those of topotypic T. ivoensis. Examination of type specimens and topotypic material of the nominal tylosaurines Hainosaurus pembinensis from the late early Campanian of Manitoba, Canada, H. gaudryi from the late Santonian or early Campanian of northwestern France, and H. lonzeensis from the Coniacian or Santonian of Belgium, indicates that all three may be Tylosaurus. The utility of isolated tooth-crowns in mosasaur taxonomy has been hampered by the often poor quality of the published illustrations of these fossils in combination with poor stratigraphic control. All Swedish remains of T. ivoensis, including 172 marginal teeth, 6 pterygoid teeth, several jawbone fragments and 12 vertebrae, were collected from a narrow stratigraphic interval corresponding to the highest biozone in the German eight-fold division of the early Campanian, providing the first good insight into the intraspecific dental variation in a tylosaurine mosasaur.
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| 27. |
- Lindgren, M., et al.
(författare)
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Styrene emissions from the spray-up and vacuum injection processes - A quantitative comparison
- 2002
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Ingår i: AIHAJ - Journal of Occupational and Environmental Hygiene. - : Informa UK Limited. - 1529-8663 .- 2163-3711. ; 63:2, s. 184-189
-
Tidskriftsartikel (refereegranskat)abstract
- Styrene emissions were studied during manufacturing of two identical glass-fiber reinforced plastic boats by two different manufacturing methods. The manufacturing methods were spray-up, which is an open method, and vacuum injection, which is a closed method. Changing the manufacturing process from an open method to a closed method decreased the styrene evaporation dramatically in this particular case. By using vacuum injection, the styrene emission during the laminate application was reduced by 98% compared with the styrene emission during laminate application by spray-up. Gel coat application by spraying will remain a major source for styrene emissions. The greatest environmental benefit is achieved with closed manufacturing methods when products without gel coat are made. The whole manufacturing process can then be performed in a closed system virtually free from emissions.
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| 28. |
- Lindgren, Per, et al.
(författare)
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Low power optimization technique for BDD mapped circuits
- 2001
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Ingår i: Proceedings of the ASP-DAC 2001, Asia and South Pacific Design Automation Conference 2001. - Piscataway, NJ : IEEE Communications Society. - 0780366336 ; , s. 615-621
-
Konferensbidrag (refereegranskat)abstract
- The minimization of power consumption is an important design constraint for circuits used in portable devices. The switching activity of a circuit node in a CMOS digital circuit directly contributes to overall power dissipation. By approximating the switching activity of circuit nodes as internal switching probabilities in binary decision diagrams (BDDs), it is possible to estimate the dynamic power dissipation characteristic of circuits resulting from a structural mapping of a BDD. A technique for minimizing the overall sum of switching probabilities is presented. The method is based on efficient local operations on a BDD representing the functionality of the circuit to be realized. The resulting circuit that is obtained by mapping the BDD to CMOS pass transistors has in simulation (using a commercially available process model) shown reduced power dissipation characteristic. Experimental results on a set of MCNC benchmarks are given for this technique
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| 29. |
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| 30. |
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| 31. |
- Nyström, Andreas, et al.
(författare)
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Porphyrin-Cored 2,2-Bis(methylol)propionic Acid Dendrimers
- 2004
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Ingår i: Chemistry of Materials. - : American Chemical Society (ACS). - 0897-4756 .- 1520-5002. ; 16:14, s. 2794-2804
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Tidskriftsartikel (refereegranskat)abstract
- The synthesis and characterization of dendron-coated porphyrins up to the fifth generation are described. Both free base and zinc-cored tetraphenylporphyrin (TPPH2 and TPPZn) were used, from which the dendrons were divergently grown using the anhydride of acetonide-protected bis-MPA (acetonide-2,2-bis(methoxy)propanoic anhydride). It is shown that a spacer must be attached to the porphyrin to increase the hydrolytic stability and allow synthesis of higher generations. Direct coupling of dendrons to the porphyrins was also investigated but failed to give full substitution of the porphyrin core. The absorption and fluorescence emission data for the TPPZn dendrimers indicate that the porphyrin configuration may change at higher generations. The hydrodynamic volume of the dendrimers is calculated from the polarization anisotropy decay data. It is shown that these bis-MPA dendrimers are significantly smaller than the same generation Frechet-type benzyl ether TPP dendrimer.
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| 32. |
- Ortegren, J., et al.
(författare)
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Improved thermal stability of pyroelectric polymers by crosslinking of ferroelectric liquid crystals
- 2001
-
Ingår i: Journal of Physical Chemistry B. - : American Chemical Society (ACS). - 1089-5647 .- 1520-6106 .- 1520-5207. ; 105:42, s. 10223-10227
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Tidskriftsartikel (refereegranskat)abstract
- Monofunctional ferroelectric liquid crystalline monomers and a blend of monofunctional/lbifunctional ferroelectric liquid crystalline monomers were photopolymerized, yielding a side-chain liquid crystalline polymer and a cross-linked polymer, respectively. The cross-linked polymer exhibited higher thermal stability than the side-chain liquid crystalline polymer and was pyroelectric up to 170 degreesC, whereas the side-chain liquid crystalline polymer lost most of its pyroelectricity at 38 degreesC. It is shown by electrooptic and birefringence measurements that cross-linking in the unwound SmC* phase prevented the reoccurrence of the helical superstructure.
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| 33. |
- Osterlund, Maria, et al.
(författare)
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Probing inhibitor-induced conformational changes along the interface between tissue factor and factor VIIa
- 2001
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Ingår i: Biochemistry. - : American Chemical Society (ACS). - 0006-2960 .- 1520-4995. ; 40:31, s. 9324-9328
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Tidskriftsartikel (refereegranskat)abstract
- Upon injury of a blood vessel, activated factor VII (FVIIa) forms a high-affinity complex with its allosteric regulator, tissue factor (TF), and initiates blood clotting. Active site-inhibited factor VIIa (FVIIai) binds to TF with even higher affinity. We compared the interactions of FVIIai and FVIIa with soluble TF (sTF). Six residues in sTF were individually selected for mutagenesis and site-directed labeling. The residues are distributed along the extensive binding interface, and were chosen because they are known to interact with the different domains of FVIIa. Fluorescent and spin probes were attached to engineered Cys residues to monitor local changes in hydrophobicity, accessibility, and rigidity in the sTF-FVIIa complex upon occupation of the active site of FVIIa. The results show that inhibition of FVIIa caused the structures around the positions in sTF that interact with the protease domain of FVIIa to become more rigid and less accessible to solvent. Thus, the presence of an active site inhibitor renders the interface in this region less flexible and more compact, whereas the interface between sTF and the light chain of FVIIa is unaffected by active site occupancy.
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| 34. |
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| 35. |
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| 36. |
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| 37. |
- Stenberg, Georg, 1947-, et al.
(författare)
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Semantic processing without conscious identification : evidence from event-related potentials
- 2000
-
Ingår i: Journal of Experimental Psychology. Learning, Memory and Cognition. - 0278-7393 .- 1939-1285. ; 26:4, s. 973-1004
-
Tidskriftsartikel (refereegranskat)abstract
- Three event-related potential (ERP) experiments examined whether semantic content can be accessed from visually presented words that cannot be consciously identified. Category labels were shown to participants, followed by masked, briefly exposed words that were either exemplars of the category or not exemplars. The task was to verify the category, by guessing if necessary, and to identify the word, naming it if possible. Exposure durations were selected to allow identification in approximately half the trials. For identified words, there was a marked difference in the ERP response between in-category and out-of category words because of an N400 component. For unidentified words, there was a similar although smaller difference. Conscious identification was defined using a variety of approaches: verbal report, 6-alternative forced choice, and binary categorization (in the context of the regression method; A. G. Greenwald, M. R. Klinger, & E. S. Schuh, 1995). By any definition, ERPs for unidentified words showed evidence of semantic processing. In addition, there were differences in the neuronal populations recruited to process above-threshold versus below-threshold words, suggesting qualitative differences.
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| 38. |
- Stenberg, Georg, et al.
(författare)
-
Semantic processing without conscious identification: Evidence from event-related potentials
- 2000
-
Ingår i: Journal of Experimental Psychology: Learning, Memory, and Cognition. - 0278-7393. ; 26, s. 973-1004
-
Tidskriftsartikel (refereegranskat)abstract
- Three event-related potential (ERP) experiments examined whether semantic content can be accessed From visually presented words that cannot he consciously identified. Category labels were shown to participants, followed by masked, briefly exposed words that were either exemplars of the category or not exemplars. The task was to verify the category, by guessing if necessary, and to identify the word naming it if possible. Exposure durations were selected to allow identification in approximately half the trials. For identified words, there was a marked difference in the ERP response between in-category and out-of-category words because of an N400 component. For unidentified words, there was a similar although smaller difference. Conscious identification was defined using a variety of approaches: verbal report 6-alternative forced choice, and binary categorization (in the context of the regression method; A. G. Greenwald, M. R. Klinger, & E. S. Schuh, 1995). By any definition, ERPs for unidentified words showed evidence of semantic processing. In addition, there were differences in the neuronal populations recruited to process above-threshold versus below-threshold words, suggesting qualitative differences.
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| 39. |
- Tarawneh, Hamed, et al.
(författare)
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Lattice Studies For The MAX-IV Storage Rings
- 2004
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Ingår i: European Particle Accelerator Conference, EPAC2004, Lucerne, Switzerland.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 40. |
- Tarawneh, Hamed, et al.
(författare)
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MAX-IV lattice, dynamic properties and magnet system
- 2003
-
Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 508:3, s. 480-486
-
Tidskriftsartikel (refereegranskat)abstract
- At MAX-LAB the next synchrotron light source MAX-IV is currently studied (Proceedings of the seventh European Particle Accelerator Conference, EPAC 02, Paris, France, 2002). In this paper, we present a possible lattice with horizontal emittance of 1.2 nm rad at an energy of 3 GeV. The possibilities to realise the main magnetic system with high gradient integrated magnets are studied with 2D and 3D magnetic field programs. The dynamic properties for the lattice are also studied and some higher order corrections are discussed. (C) 2003 Elsevier B.V. All rights reserved.
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| 41. |
- Tiihonen, Mikael, et al.
(författare)
-
A compact OPO/SFG laser for ultraviolet biological sensing : TECHNOLOGY AND DEVICES
- 2004
-
Ingår i: SOLID STATE LASERS XIII. - BELLINGHAM : SPIE-INT SOC OPTICAL ENGINEERING. - 0819452408 ; , s. 134-142
-
Konferensbidrag (refereegranskat)abstract
- A compact parametric oscillator (OPO) with intracavity sum-frequency generation (SFG) to generate 293 nm UV laser irradiation, was developed. The OPO/SFG device was pumped by a 100 Hz Nd:YAG laser (1064 nm) of own design, including subsequent second harmonic generation (SHG) in an external periodically poled KTiOPO4 (KTP) crystal. The whole system could be used to deliver more than 30 muJ laser irradiation per pulse (100 Hz) at 293 nm. The UV laser light was introduced in an optical fiber attached to a sample compartment allowing detection of fluorescence emission using a commercial spectrometer. Aqueous samples containing biomolecules (ovalbumin) or bacteria spores (Bacillus subtilis) were excited by the UV-light at 293 nm resulting in strong fluorescence emission in the range 325-600 nm.
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| 42. |
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| 43. |
- Tiihonen, Mikael, et al.
(författare)
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A novel UV-laser source for fluorescence excitation of proteins
- 2004
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Ingår i: OPTICALLY BASED BIOLOGICAL AND CHEMICAL SENSING FOR DEFENCE. - BELLINGHAM : SPIE-INT SOC OPTICAL ENGINEERING. - 0819455709 ; , s. 261-268
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Konferensbidrag (refereegranskat)abstract
- A novel, compact and robust UV laser has been developed for laser induced fluorescence spectroscopy of biomolecules in the spectral region from 290 nm to 345 nm. It was based on a frequency-doubled passively Q-switched Nd:YAG laser. emitting at 53 2 nm, which was pumping a periodically poled KTiOPO4 optical parametric oscillator with intra-cavity sum-frequency mixing in a 13130 crystal. The output was generated in two branches in the UV, 293 mn and 343 nm, with pulse widths of 1.8 ns and pulse repetition rate of 100 Hz. These wavelengths were then used for fluorescence experiments of bioagents.
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| 47. |
- von Haartman, Martin, et al.
(författare)
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1/f noise in Si and Si0.7Ge0.3 pMOSFETs
- 2003
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Ingår i: IEEE Transactions on Electron Devices. - 0018-9383 .- 1557-9646. ; 50, s. 2513-2519
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Tidskriftsartikel (refereegranskat)abstract
- Strained layer Si0.7Ge0.3 pMOSFETs were fabricated and shown to exhibit enhanced hole mobility, up to 35% higher for a SiGe device with 3-nm-thick Si-cap, and lower 1/f noise compared to Si surface channel pMOSFETs. The 1/f noise in the investigated devices was dominated by mobility fluctuation noise and found to be lower in the SiGe devices. The source of the mobility fluctuations was determined by investigating the electric field dependence of the 1/f noise. It was found that the SiO2/Si interface roughness scattering plays an important role for the mobility fluctuation noise, although not dominating the effective mobility. The physical separation of the carriers from the SiO2/Si interface in the buried SiGe channel pMOSFETs resulted in lower SiO2/Si interface roughness scattering, which explains the reduction of 1/f noise in these devices. The 1/f noise mechanism was experimentally verified by studying 1/f noise in SiGe devices with various thicknesses of the Si-cap. A too large Si-cap thickness led to a deteriorated carrier confinement in the SiGe channel resulting in that considerable 1/f noise was generated in the parasitic current in the Si-cap. In our experiments, the SiGe devices with a Si-cap thickness in the middle of the interval 3-7 nm exhibited the lowest 1/f noise.
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| 48. |
- von Haartman, Martin, et al.
(författare)
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Influence of gate width on 50 nm gate length Si0.7Ge0.3 channel PMOSFETs
- 2003
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Ingår i: ESSDERC 2003: PROCEEDINGS OF THE 33RD EUROPEAN SOLID-STATE DEVICE RESEARCH CONFERENCE. ; , s. 529-532
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Konferensbidrag (refereegranskat)abstract
- Compressively strained Si0.7Ge0.3 channel pMOSFETs were fabricated and the effective hole mobility was found to be 20-30% higher in the Si0.7Ge0.3 devices than in their Si counterparts. The g(m,) normalized to gate width, was found to increase strongly with decreasing gate width in the Si0.7Ge0.3 devices, a behavior that was not found in the Si devices. All the Si0.7Ge0.3 devices down to 50 nm gate length showed enhanced g. compared to the Si devices for gate widths <1 um. At L = 50 nm and W = 0.25 mum the Si0.7Ge0.3 devices exhibited increased g(m) and I-D of about 15 %, in saturation, compared to the Si devices. I-on was 286 muA/mum and I-off was 0.23 nA/mum at V-dd = 1.5 Vfor the Si0.7Ge0.3 device.
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| 49. |
- Walther, Sten, et al.
(författare)
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Antibiotic prescription practices, consumption and bacterial resistance in a cross section of Swedish intensive care units
- 2002
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Ingår i: Acta Anaesthesiologica Scandinavica. - : Wiley. - 0001-5172. ; 46:9, s. 1075-1081
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Tidskriftsartikel (refereegranskat)abstract
- Background: The purpose of this work was to study usage of antibiotics, its possible determinants, and patterns of bacterial resistance in Swedish intensive care units (ICUs). Methods: Prospectively collected data on species and antibiotic resistance of clinical isolates and antibiotic consumption specific to each ICU in 1999 were analyzed together with answers to a questionnaire. Antibiotic usage was measured as defined daily doses per 1000 occupied bed days (DDD1000). Results: Data were obtained for 38 ICUs providing services to a population of approximately 6 million. The median antibiotic consumption was 1257 DDD1000 (range 584–2415) and correlated with the length of stay but not with the illness severity score or the ICU category. Antibiotic consumption was higher in the ICUs lacking bedside devices for hand disinfection (2193 vs. 1214 DDD1000, p=0.05). In the ICUs with a specialist in infectious diseases responsible for antibiotic treatment the consumption pattern was different only for use of glycopeptides (58% lower usage than in other ICUs: 26 vs. 11 DDD1000,P=0.02). Only 21% of the ICUs had a written guideline on the use of antibiotics, 57% received information on antibiotic usage at least every 3 months and 22% received aggregated resistance data annually. Clinically significant antimicrobial resistance was found among Enterbacter spp. to cephalosporins and among Enterococcus spp. to ampicillin. Conclusions: Availability of hand disinfection equipment at each bed and a specialist in infectious diseases responsible for antibiotic treatment were factors that correlated with lower antibiotic consumption in Swedish ICUs, whereas patient-related factors were not associated with antibiotic usage.
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| 50. |
- Wu, D., et al.
(författare)
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A novel strained Si0.7Ge0.3 surface-channel pMOSFET with an ALD TiN/Al2O3/HfAlOx/Al2O3 gate stack
- 2003
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Ingår i: IEEE Electron Device Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 0741-3106 .- 1558-0563. ; 24:3, s. 171-173
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Tidskriftsartikel (refereegranskat)abstract
- Proof-of-concept pMOSFETs with a strained-Si0.7Ge0.3 surface-channel deposited by selective epitaxy and a TiN/Al2O3/HfAIO(x)/Al2O3 gate stack grown by atomic layer chemical vapor deposition (ALD) techniques were fabricated. The Si0.7Ge0.3 pMOSFETs exhibited more than 30% higher current drive and peak transconductance than reference Si pMOSFETs with the same gate stack. The effective mobility for the Si reference coincided with the universal hole mobility curve for Si. The presence of a relatively low density of interface states, determined as 3.3x10(11) cm(-2) eV(-1), yielded a subthreshold slope of 75 mV/dec. for the Si reference. For the Si0.7Ge0.3 pMOSFETs, these values were 1.6x10(12) cm(-2) eV(-1) and 110 mV/dec., respectively.
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