| 1. |
- Gustavsson, Ingvar, et al.
(author)
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A Remote Laboratory providing Teacher-defined Sessions
- 2004
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Conference paper (other academic/artistic)abstract
- An experiment server emulating a traditional university laboratory for courses in Circuit Analysis and Electronics has been set up at Blekinge Institute of Technology (BTH) in Ronneby, Sweden. Students in different places around the globe can participate in lab sessions allowing up to eight client PCs to be connected to the server via the Internet simultaneously or they can perform experiments alone without supervision around the clock when the laboratory is not fully occupied. Regular sessions are supervised by one instructor using MS Netmeeting or other means of communication. The laboratory pro-vides common instruments and the user interface is in English but universities or other learning organizations engaging the laboratory for their courses can use lab instruction manuals and other learning material in a language of their choice. In a traditional labora-tory the students use a breadboard and components handed over by the instructor to form the circuits assigned and connect the test probes. In the remote laboratory a virtual breadboard and photographs of the components provided in each session are displayed on the client PC screen at startup. The students use the mouse to locate each virtual component on the breadboard and do the wiring to assemble the circuits. The teacher or someone in the laboratory staff mounts the corresponding real components in sockets in a switching matrix in Ronneby controlled by the virtual breadboard routine before the session. The instruments provided are computer-based and have virtual front panels. The time sharing scheme used to allow simultaneous access to one server imposes re-strictions on the time period allowed for each experiment but in courses in electronics the time constants involved can without any inconvenience be selected within a proper range. The number of nodes on the virtual breadboard is also limited due to the hard-ware complexity of the switching matrix but is adequate for experiments in undergradu-ate education. Apart from the fact that each student or student team is working in a vir-tual environment without face to face contact with the instructor or other students in the laboratory the only difference compared to a traditional lab session is that it is not pos-sible for a student to manipulate the components and the wires with their fingers. The laboratory is always open and can be used by everybody outside regular lab sessions. Only a 56 kbit/s modem and MS Internet Explorer are required. The client software can be downloaded from the laboratory web site. The address of the homepage of the ex-periment server is: http://distanslabserver.its.bth.se/. In this paper laboratory sessions in the remote laboratory will be compared with sessions in a traditional laboratory.
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| 2. |
- Hagberg, Henrik, 1955, et al.
(author)
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PARP-1 gene disruption in mice preferentially protects males from perinatal brain injury
- 2004
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In: J Neurochem. ; 90:5, s. 1068-75
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Journal article (peer-reviewed)abstract
- Poly(ADP-ribose) polymerase-1 is over-activated in the adult brain in response to ischemia and contributes to neuronal death, but its role in perinatal brain injury remains uncertain. To address this issue, 7-day-old wild-type (wt) and PARP-1 gene deficient (parp+/- and parp-/-) Sv129/CD-1 hybrid mice were subjected to unilateral hypoxia-ischemia and histologic damage was assessed 10 days later by two evaluators. Poly(ADP-ribose) polymerase-1 knockout produced moderate but significant (p < 0.05) protection in the total group of animals, but analysis by sex revealed that males were strongly protected (p < 0.05) in contrast to females in which there was no significant effect. Separate experiments demonstrated that PARP-1 was activated over 1-24 h in both females and males after the insult in neonatal wt mice and rats using immnocytochemistry and western blotting for poly(ADP-ribose). Brain levels of NAD+ were also significantly reduced, but the decrease of NAD+ during the early post-hypoxia-ischemia (HI) phase was only seen in males. The results indicate that hypoxia-ischemia activates Poly(ADP-ribose) polymerase-1 in the neonatal brain and that the sex of the animal strongly influences its role in the pathogenesis of brain injury.
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| 3. |
- Rönnbäck, Marie, et al.
(author)
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Combustion process in a biomass fuel bed --experimental results
- 2001
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In: Progress in Thermochemical Biomass Conversion. - 0632055332 ; 1, s. 743-757
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Conference paper (peer-reviewed)abstract
- Combustion processes in a biomass bed are investigated experimentally. Special attention is paid to the influence of primary air flow and particle properties on the ignition front, its temperature and on the composition of the gas leaving the front. Two test rigs have been built: a large rig in the same size as a domestic boiler and a small laboratory test rig. In both rigs the combustion front moves in opposite direction to the primary air flow. Two combustion regimes are identified: a sub-stoichiometric regime with complete consumption of oxygen and an over-stoichiometric regime. The results show that a fuel with higher density and thermal conductivity (but in other respects similar) has a wider sub-stoichiometric regime. If the particle size is increased the air flow range becomes shorter and starts at higher air flow.
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