| 1. |
- Lehtipalo, Katrianne, et al.
(author)
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The effect of acid-base clustering and ions on the growth of atmospheric nano-particles
- 2016
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In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 7
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Journal article (peer-reviewed)abstract
- The growth of freshly formed aerosol particles can be the bottleneck in their survival to cloud condensation nuclei. It is therefore crucial to understand how particles grow in the atmosphere. Insufficient experimental data has impeded a profound understanding of nano-particle growth under atmospheric conditions. Here we study nano-particle growth in the CLOUD (Cosmics Leaving OUtdoors Droplets) chamber, starting from the formation of molecular clusters. We present measured growth rates at sub-3 nm sizes with different atmospherically relevant concentrations of sulphuric acid, water, ammonia and dimethylamine. We find that atmospheric ions and small acid-base clusters, which are not generally accounted for in the measurement of sulphuric acid vapour, can participate in the growth process, leading to enhanced growth rates. The availability of compounds capable of stabilizing sulphuric acid clusters governs the magnitude of these effects and thus the exact growth mechanism. We bring these observations into a coherent framework and discuss their significance in the atmosphere.
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| 2. |
- Austrin, Per, et al.
(author)
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Space-time tradeoffs for subset sum : An improved worst case algorithm
- 2013
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In: Automata, Languages, and Programming. - Berlin, Heidelberg : Springer. - 9783642392054 ; , s. 45-56
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Conference paper (peer-reviewed)abstract
- The technique of Schroeppel and Shamir (SICOMP, 1981) has long been the most efficient way to trade space against time for the Subset Sum problem. In the random-instance setting, however, improved tradeoffs exist. In particular, the recently discovered dissection method of Dinur et al. (CRYPTO 2012) yields a significantly improved space-time tradeoff curve for instances with strong randomness properties. Our main result is that these strong randomness assumptions can be removed, obtaining the same space-time tradeoffs in the worst case. We also show that for small space usage the dissection algorithm can be almost fully parallelized. Our strategy for dealing with arbitrary instances is to instead inject the randomness into the dissection process itself by working over a carefully selected but random composite modulus, and to introduce explicit space-time controls into the algorithm by means of a "bailout mechanism".
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| 3. |
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| 4. |
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| 5. |
- Schulz, J., et al.
(author)
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5p photoemission from laser excited cesium atoms
- 2006
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In: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 73:6
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Journal article (peer-reviewed)abstract
- Fine-structure resolved 5p photoemission spectra of Cs in the ground state and after laser excitation into the [Xe]6p P-2(1/2) and 6p(2)P(3/2) states have been studied. The 5p(5)6p final states have been reached by the 5p(6)6s -> 5p(5)6p conjugate shakeup process from ground-state atoms as well as by direct photoemission from laser-excited atoms. The laser-excited spectra can be well described with calculations based on the jK-coupling model. Calculations based on a multiconfiguration Dirac-Fock approach have been performed to investigate the deviations created by intermediate coupling from the pure jK-coupling scheme.
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| 6. |
- Stedt, H, et al.
(author)
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Tomato thymidine kinase-based suicide gene therapy for malignant glioma-an alternative for Herpes Simplex virus-1 thymidine kinase.
- 2015
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In: Cancer Gene Therapy. - : Springer Science and Business Media LLC. - 1476-5500 .- 0929-1903. ; 22:3, s. 130-137
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Journal article (peer-reviewed)abstract
- Malignant gliomas (MGs) are the most common malignant primary brain tumors with a short life estimate accompanied by a marked reduction in the quality of life. Herpes Simplex virus-1 thymidine kinase ganciclovir (HSV-TK/GCV) system is the best characterized enzyme prodrug therapy in use. However, lipophobicity of GCV and low enzymatic activity of HSV-TK reduce the treatment efficacy. Tomato TK (ToTK) has shown high activity in combination with its specific substrate azidothymidine (AZT). The aim of this study was to evaluate whether ToTK/AZT could be used as an alternative to HSV-TK/GCV therapy. Both treatments demonstrated cytotoxicity in human MG cells in vitro. In vivo, both treatments decreased tumor growth and tumors were smaller in comparison with controls in mouse orthotopic MG model. Survival of ToTK/AZT-treated mice was significantly increased compared with control mice (*P<0.05) but not as compared with HSV-TK/GCV-treated mice. No significant differences were observed in clinical chemistry safety analyses. We conclude that both treatments showed a beneficial treatment response in comparison to controls on tumor growth and ToTK/AZT also on survival. There were no significant differences between these treatments. Therefore ToTK/AZT could be considered as an alternative treatment option for MG because of its favorable therapeutic characteristics.Cancer Gene Therapy advance online publication, 23 January 2015; doi:10.1038/cgt.2014.76.
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| 7. |
- van Laere, Joeri, 1974-, et al.
(author)
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Mitigating Escalation of Cascading Effects of a Payment Disruption across other Critical Infrastructures : Lessons Learned in 15 Simulation-Games
- 2019
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In: Proceedings of the 14th International Conference on Critical Information Infrastructures Security (CRITIS) 2019. - Linköping : Linköping University.
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Conference paper (peer-reviewed)abstract
- A disruption in one critical infrastructure can quickly lead to cascading effects in several other ones. Much research has been done to analyze dependencies between different critical infrastructures, but little is known about how to mitigate escalation and cascading effects across several critical infrastructures, i.e. how to develop collective critical infrastructure resilience. This research presents the results of 15 simulation-games where groups of 6 to 8 field experts from different sectors were challenged to collaboratively manage a disruption in the payment system that quickly affected food distribution, fuel distribution, transport, health care et cetera. Teams discussed possible strategies, which next were implemented in a computer simulation. Teams could influence the sequence of events on 4 decision points during a 10 day scenario, and play the same scenario several times to test alternative solutions. Each simulation-game session lasted a full day. Data analysis involved the recorded team discussions as well as computer simulation logs of the implemented decisions and their impacts. The results show how escalation and the severity of cascading effects largely depends on the quality of the early crisis response and not so much on the initial disruption. Also, it is shown how cross sectorial collaboration is required. Responses where groups focus too much on cascading effects in one area lead too poor overall performance for society at large. Groups tend to overbalance their mitigating strategies initially, until they arrive at a more balanced strategy that covers challenges in several different critical infrastructures from an integral perspective.
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