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Coronal mass ejections (CMEs) originate from closed magnetic field regions on the Sun, which are active regions and quiescent filament regions. The energetic populations such as halo CMEs, CMEs associated with magnetic clouds, geoeffective CMEs, CMEs associated with solar energetic particles and interplanetary type II radio bursts, and shock-driving CMEs have been found to originate from sunspot regions. The CME and flare occurrence rates are found to be correlated with the sunspot number, but the correlations are significantly weaker during the maximum phase compared to the rise and declining phases. We suggest that the weaker correlation results from high-latitude CMEs from the polar crown filament regions that are not related to sunspots. [ABSTRACT FROM AUTHOR]

Ion-mobility spectrometry offers a robust and effective technique to detect ion clusters. Here, influence of temperature on the ion cluster formation has been measured. Especially temperatures below 0°C favor formation of dimers and trimers for the 2-propanol used as a trace compound. Keywords Ion clusters, ion-mobility spectrometry, time-of-flight [ABSTRACT FROM AUTHOR]

The link between ambient biogenic volatile organic compounds (VOCs) and secondary new particle formation has been hypothesized for a long time. However no clear indication for the participation in the very first steps has been found yet. In this study we link atmospheric air ion concentrations between 0.56 and 0.75 nm in mobility-derived diameter to a first stage oxidation product of sesquiterpenes, the C15-stabilized Criegee intermediates. These intermediates, which are obtained from air ion measurements at Hyytiälä (Finland), react subsequently with either sulphuric acid to form organo sulfates or with pinonaldehyde producing secondary ozonides to initiate new particle formation. Assuming activation to occur by reactive sulphuric acid uptake, we calculated new particle formation rates observed during the BACCI/QUEST IV campaign and found a good match between the calculated and the measured ones. However, the height of new particle formation is dependent on the stability of the boundary layer and the resulting vertical profile of sesquiterpenes. The nice agreement between measurements and calculations provide a first indication about the importance of the biosphere with respect to nucleation and a further feedback within the climate system. Keywords Heterogeneous nucleation, sesquiterpenes, sulphuric acid, boreal forest [ABSTRACT FROM AUTHOR]

Mobile phones have evolved from voice-centric communication devices to powerful personal multimedia devices. Among other multimedia features, they enable the users to capture video clips with built-in digital cameras. However, due to the continuous nature of video, it is often difficult to capture a video clip exactly as intended - in many cases the possibility to edit the clip after capture would be useful. We describe the design of a video editor application for mobile devices. We present the main user goals for video editing in the mobile context based on a Contextual Inquiry study and an application design that supports these goals. We demonstrate that video editing on mobile devices is feasible and report a usability evaluation with encouraging results. [ABSTRACT FROM AUTHOR]

The need for authenticating users of ubiquitous mobile devices is becoming ever more critical with the increasing value of information stored in the devices and of services accessed via them. Passwords and conventional biometrics such as fingerprint recognition offer fairly reliable solutions to this problem, but these methods require explicit user authentication and are used mainly when a mobile device is being switched on. Furthermore, conventional biometrics are sometimes perceived as privacy threats. This paper presents an unobtrusive method of user authentication for mobile devices in the form of recognition of the walking style (gait) and voice of the user while carrying and using the device. While speaker recognition in noisy conditions performs poorly, combined speaker and accelerometer-based gait recognition performs significantly better. In tentative tests with 31 users the Equal Error Rate varied between 2% and 12% depending on noise conditions, typically less than half of the Equal Error Rates of individual modalities. [ABSTRACT FROM AUTHOR]

Model checking by exhaustive state space enumeration is one of the most developed analysis methods for distributed event systems. Its main problem—the size of the state spaces—has been addressed by various reduction methods. Complex systems tend to consist of loosely connected modules, which may perform internal tasks in parallel. The possible interleavings of these parallel tasks easily leads to a large number of reachable global states. In modular state space analysis, the internal actions are explored separately in each module, and the global state space only includes synchronisations. This article introduces nested modular nets, which are hierarchal collections of nets synchronising via shared transitions, and presents a simple algorithm for model checking safety properties in modular systems. [ABSTRACT FROM AUTHOR]

PCR (polymerase chain reaction)products are conventionally detected by agarose gel electrophoresis and ethidium bromide staining.However, the specificity and sensitivity of detection can be increased by hybridization with a labeled probe that is complementary to an internal sequence in the amplified target.Time-resolved fluorometry (TRF)utilizes nonradioactive lanthanide chelates with large Stoke's shifts as the labels (1).For the time-resolved measurement of lanthanide fluorescence, a fluorometer is used (e.g., those manufactured by Wallac)that has a xenon flash lamp at 340-nm wavelength with 1-s intervals between flashes.After the excitation light flash and a delay time of 0.4 s, the emission from the lanthanides is measured at longer wave-lengths (613,643, and 545 nm for Eu, Sm3+, and Tb3+, respectively)for another 0.4 s.The excitation-emission measurement cycles are repeated 1000 × during a total measurement time of 1 s per sample. The lanthanides, e.g., europium (Eu3+), samarium (Sm3+) and terbium (Tb3+), have manifold longer fluorescence lifetimes than most biological compounds.A time delay after the excitation pulse eliminates nonspecific background by allowing the short-lived autofluores-cence of the biological material to decline to an insignificant level before measuring the specific signals from the lanthanides (2).This delay time is the time-resolving principle and combined together with large Stoke's shifts, it is the critical element that makes TRF such a sensitive technique.Substances with the same fluorescence characteristics as lanthanides are rarely, if ever, found in natural samples, and background from rare earth metals is also very low. The fluorescence signals obtained are directly proportional to the amount of probe bound and captured on a solid phase in assays that are conveniently performed in a microtiter-plate format.Furthermore, the different emission wavelengths of the lanthanide chelates have permitted the development of multi-label assays.By using different fluorescence filters for detection, the labels can be easily distinguished from each other in an individual hybridization reaction. [ABSTRACT FROM AUTHOR]