Personas in Uniform: Police Officers as Users of Information Technology

This paper discusses information technology in the contemporary policing context and presents a research approach that aims to capture and describe a multifaceted account of police work. There is a need to further analyze the constitution of the uniformed user and the use environment in this domain. Data from extensive ethnographic fieldwork are analyzed. Personas and scenarios are used in this paper to illustrate the properties and conditions of police work. Evidence from the study suggests that personas and scenarios can make the daily work visible and support the emergent design of information systems in the dialogue between designers and users. The paper concludes that personas and their scenarios provide a richer description of the specifics of a context and a design space. A scenario is used to show characteristic properties and the emergence of work practice in relation to the design of information systems

Evaluation of technical approaches to pronuclei injection

The transgenic technology makes it possible to introduce specific genetic alterations into the genome of all cells in an organism. This has opened entirely new possibilities to analyse the regulation and function of individual genes in a living  animal. We have established a facility for the production of transgenic mice and have generated 37 different transgenic mouse strains. Here we analyse if the frequency of transgenic offspring correlates with the length of the introduced transgene and/or with the genetic background of the injected eggs. Our data suggest that the transgenic frequency is relatively independent of the length of the construct. The genetic background is more important and we find that specific steps in the process of generating transgenic mice are considerably more efficient in an F2 intercross between C57BL6 and CBA than in inbred C57BL6 mice. Finally we discuss how we have used the transgenic technology to analyse the regulation and function of genes inthe developing nervous system

Level of confidence evaluation and its usage for Roll-back Recovery with Checkpointing optimization

Increasing soft error rates for semiconductor devices manu- factured in later technologies enforces the use of fault tolerant techniques such as Roll-back Recovery with Checkpointing (RRC). However, RRC introduces time overhead that increases the completion (execution) time. For non-real-time systems, research have focused on optimizing RRC and shown that it is possible to find the optimal number of checkpoints such that the average execution time is minimal. While minimal average execution time is important, it is for real-time systems important to provide a high probability that deadlines are met. Hence, there is a need of probabilistic guarantees that jobs employing RRC complete before a given deadline. First, we present a mathematical framework for the evaluation of level of confidence, the probability that a given deadline is met, when RRC is employed. Second, we present an optimization method for RRC that finds the number of checkpoints that results in the minimal completion time while the minimal com- pletion time satisfies a given level of confidence requirement. Third, we use the proposed framework to evaluate probabilistic guarantees for RRC optimization in non-real-time systems

Simulated productivity of conceptual, multi-headed tree planting devices

Mechanized tree planting is presently enjoying a revival in Fennoscandia with increased focus on further technical development. To explore the productivity effect of multiple heads on crane-mounted tree planting devices, we used a discrete-event simulation tool in which excavator-mounted one- to four-headed devices reforested clearcuts with variable frequencies of obstacles. During the simulations, the device models either mounded or inverted soil and then planted seedlings. A planting head could be hindered by stones and roots from performing these tasks, thus causing queuing delays for multi-headed devices. Surface boulders, stumps, and humus layers also slowed down the work. The results showed that productivity increased significantly with increasing numbers of planting heads on terrain with sparse or moderate obstacles, regardless of using faster or slower soil preparation methods or seedling reloading systems. However, on obstacle-rich terrain, three-headed planting devices were more productive than four-headed, while one-headed were as equally productive as twoheaded devices. Obstacle-rich terrain sometimes inhibited those large four-headed devices from planting even one seedling at a given machine stationary point. Therefore, we conclude that three planting heads per cranemounted device seems to be the most realistic configuration for combining high productivity with good silvicultural results on all the terrain types that a planting machine might work on in Fennoscandia. Future studies should investigate the silvicultural effects of different tree spacing geometries and the corresponding suitable geometrical design of three-headed crane-mounted planting devices

Achieving translational symmetry in trapped cold ion rings

Spontaneous symmetry breaking is a universal concept throughout science. For instance, the Landau-Ginzburg paradigm of translational symmetry breaking underlies the classification of nearly all quantum phases of matter and explains the emergence of crystals, insulators, and superconductors. Usually, the consequences of translational invariance are studied in large systems to suppress edge effects which cause undesired symmetry breaking. While this approach works for investigating global properties, studies of local observables and their correlations require access and control of the individual constituents. Periodic boundary conditions, on the other hand, could allow for translational symmetry in small systems where single particle control is achievable. Here, we crystallize up to fifteen 40Ca+ ions in a microscopic ring with inherent periodic boundary conditions. We show the ring's translational symmetry is preserved at millikelvin temperatures by delocalizing the Doppler laser cooled ions. This establishes an upper bound for undesired symmetry breaking at a level where quantum control becomes feasible. These findings pave the way towards studying quantum many-body physics with translational symmetry at the single particle level in a variety of disciplines from simulation of Hawking radiation to exploration of quantum phase transitions.Comment: 15 pages, 4 figure

Purification and characterization of two protein kinases acting on the aquaporin SoPIP2;1

AbstractAquaporins are water channel proteins that facilitate the movement of water and other small solutes across biological membranes. Plants usually have large aquaporin families, providing them with many ways to regulate the water transport. Some aquaporins are regulated post-translationally by phosphorylation. We have previously shown that the water channel activity of SoPIP2;1, an aquaporin in the plasma membrane of spinach leaves, was enhanced by phosphorylation at Ser115 and Ser274. These two serine residues are highly conserved in all plasma membrane aquaporins of the PIP2 subgroup. In this study we have purified and characterized two protein kinases phosphorylating Ser115 and Ser274 in SoPIP2;1. By anion exchange chromatography, the Ser115 kinase was purified from the soluble protein fraction isolated from spinach leaves. The Ca2+-dependent Ser274 kinase was purified by peptide affinity chromatography using plasma membranes isolated from spinach leaves. When characterized, the Ser115 kinase was Mg2+-dependent, Ca2+-independent and had a pH-optimum at 6.5. In accordance with previous studies using the oocyte expression system, site-directed mutagenesis and kinase and phosphatase inhibitors, the phosphorylation of Ser274, but not of Ser115, was increased in the presence of phosphatase inhibitors while kinase inhibitors decreased the phosphorylation of both Ser274 and Ser115. The molecular weight of the Ser274 kinase was approximately 50 kDa. The identification and characterization of these two protein kinases is an important step towards elucidating the signal transduction pathway for gating of the aquaporin SoPIP2;1