Relativistic microburst storm characteristics: Combined satellite and ground-based observations

We report a comparison of Solar Anomalous Magnetospheric Particle Explorer detected relativistic electron microbursts and short-lived subionospheric VLF perturbations termed FAST events, observed at Sodankyl Geophysical Observatory, Finland, during 2005. We show that only strong geomagnetic disturbances can produce FAST events, which is consistent with the strong link between storms and relativistic microbursts. Further, the observed FAST event perturbation decay times were consistent with ionospheric recovery from bursts of relativistic electron precipitation. However, the one-to-one correlation in time between microbursts and FAST events was found to be very low (similar to 1%). We interpret this as confirmation that microbursts have small ionospheric footprints and estimate the individual precipitation events to be <4 km radius. In contrast, our study strongly suggests that the region over which microbursts occur during storm event periods can be at least similar to 90 degrees in longitude (similar to 6 h in magnetic local time). This confirms earlier estimates of microburst storm size, suggesting that microbursts could be a significant loss mechanism for radiation belt relativistic electrons during geomagnetic storms. Although microbursts are observed at a much higher rate than FAST events, the ground-based FAST event data can provide additional insight into the conditions required for microburst generation and the time variation of relativistic precipitation

Predicting drug-target interactions through integrative analysis of chemogenetic assays in yeast

Peer reviewe

Supercurrent-induced temperature gradient across a nonequilibrium SNS Josephson junction

Using tunneling spectroscopy, we have measured the local electron energy distribution function in the normal part of a superconductor-normal metal-superconductor (SNS) Josephson junction containing an extra lead to a normal reservoir. In the presence of simultaneous supercurrent and injected quasiparticle current, the distribution function exhibits a sharp feature at very low energy. The feature is odd in energy, and odd under reversal of either the supercurrent or the quasiparticle current direction. The feature represents an effective temperature gradient across the SNS Josephson junction that is controllable by the supercurrent.Comment: 4 pages, 4 figures, corrected typos, added plot to figure

Experimentally induced community assembly of polypores reveals the importance of both environmental filtering and assembly history

The community assembly of wood-inhabiting fungi follows a successional pathway, with newly emerging resource patches being colonised by pioneer species, followed by those specialised on later stages of decay. The primary coloniser species have been suggested to strongly influence the assembly of the later-arriving community. We created an artificial resource pulse and studied the assembly of polypores over an 11yr period to ask how the identities of the colonising species depend on the environmental characteristics and the assembly history of the dead wood unit. Our results support the view that community assembly in fungi is a highly stochastic process, as even detailed description of the characteristics of dead wood (host tree species, size, decay class of the resource unit, its bark cover and how sunken it is to the ground) and the prior community structure provided only limited predictive power on the newly colonising species. Yet, we identified distinct links between primary and secondary colonising species and showed how the spatial aggregation of dead wood had a great impact on the community assembly. © 2019 Elsevier Ltd and British Mycological SocietyPeer reviewe

PhosFox : a bioinformatics tool for peptide-level processing of LC-MS/MS-based phosphoproteomic data

Peer reviewe

A new proof for the decidability of D0L ultimate periodicity

We give a new proof for the decidability of the D0L ultimate periodicity problem based on the decidability of p-periodicity of morphic words adapted to the approach of Harju and Linna.Comment: In Proceedings WORDS 2011, arXiv:1108.341

Macroscopic quantum tunneling in nanoelectromechanical systems

The experimental observation of quantum phenomena in mechanical degrees of freedom is difficult, as the systems become linear toward low energies and the quantum limit, and thus reside in the correspondence limit. Here we investigate how to access quantum phenomena in flexural nanomechanical systems which are strongly deflected by a voltage. Near a metastable point one can achieve a significant nonlinearity in the electromechanical potential at the scale of zero-point energy. The system can then escape from the metastable state via macroscopic quantum tunneling (MQT). We consider two model systems suspended atop a voltage gate, namely, a graphene sheet and a carbon nanotube. We find that the experimental demonstration of the phenomenon is currently possible but demanding, since the MQT crossover temperatures fall in the milli-Kelvin range. A carbon nanotube is suggested as the most promising system.Peer reviewe

IT investment evaluation: why hasn ’t it become an organization routine?

In this study we attempt to understand why formal evaluations of IT investment projects have not yet become an organizational routine. Using survey data gathered from business and IT managers in Sweden, we tested the research hypotheses about the factors influencing the attitudes and behaviour of managers towards using formal evaluation methods based on the theory of planned behaviour. We found that the intent to use formal evaluation methods in an organization is determined by the attitudes of the managers towards the formal methods, the common beliefs of the organization about the formal methods, and the perceived ability to perform formal evaluations. Interestingly, we found that the attitudes toward formal methods are determined mostly by the perceived usefulness of the methods and not by the perceived ease of use of these methods, suggesting that the decision to use formal methods is most likely based on rational analyses rather than individual preferences. We also found that awareness and selfefficacy contribute to the use of formal methods via influences on organizational beliefs and perceived ability to perform evaluation tasks. These findings provide some interesting managerial implications for advocating the use of formal methods in organizations