Opportunistic Content-Centric Data Transmission During Short Network Contacts

In this paper, we investigate content-centric data transmission in the context of short opportunistic contacts and base our work on an existing content-centric networking architecture. In case of short interconnection times, file transfers may not be completed and the received information is discarded. Caches in content-centric networks are used for short-term storage and do not guarantee persistence. We implemented a mechanism to extend caching on persistent storage enabling the completion of disrupted content transfers. The mechanisms have been implemented in the CCNx framework and have been evaluated on wireless mesh nodes. Our evaluations using multicast and unicast communication show that the implementation can support content transfers in opportunistic environments without significant processing and storing overhead.

The Life and Times of Bills

Time is one of the scarcest resources in modern parliaments. In parliamentary systems of government the control of time in the chamber is a significant power resource enjoyed – to varying degrees – by parliamentary majorities and the governments they support. Minorities may not be able to muster enough votes to stop bills, but they may have – varying degrees of – delaying powers enabling them to extract concessions from majorities attempting to get on with their overall legislative programme. This paper provides a comparative analysis of the dynamics of the legislative process in 17 West European parliaments from the formal initiation of bills to their promulgation. The ‘biographies’ of a sample of bills are examined using techniques of event-history analysis (a) charting the dynamics of the legislative process both across the life-times of individual bills and different political systems and (b) examining whether, and to what extent, parliamentary rules and some general regime attributes influence the dynamics of this process, speeding up or delaying the passage of legislation. Using a veto-points framework and transaction cost politics as a theoretical framework, the quantitative analyses suggest a number of counter-intuitive findings (e.g., the efficiency of powerful committees) and cast doubt on some of the claims made by Tsebelis in his veto-player model.

Unconscious word stem completion priming in a mirror-masking paradigm

The aim of this study was to investigate unconscious priming by the use of a spatial mirror-masking paradigm. Words and nonwords with no under-length letters are mirrored at their horizontal axis. The results are figures of geometric-like forms that contain letters in their upper part. In the three experiments reported in this study, a priming procedure used such mirrored words and nonwords as primes. Participants were ignorant of the nature of the construction of the stimuli. Perceptual reports of the participants revealed that they did not realize that words were hidden in the primes. Nevertheless, they showed priming in all three experiments. Priming effects were replicated with prime–target SOAs of between 1 and 3 s. Functional dissociations were found between ignorant and informed participants. Informed groups showed perceptual and semantic priming, while ignorant groups showed only perceptual priming.

Notch signaling in the brain: in good and bad times.

Notch signaling is an evolutionarily conserved pathway, which is fundamental for neuronal development and specification. In the last decade, increasing evidence has pointed out an important role of this pathway beyond embryonic development, indicating that Notch also displays a critical function in the mature brain of vertebrates and invertebrates. This pathway appears to be involved in neural progenitor regulation, neuronal connectivity, synaptic plasticity and learning/memory. In addition, Notch appears to be aberrantly regulated in neurodegenerative diseases, including Alzheimer's disease and ischemic injury. The molecular mechanisms by which Notch displays these functions in the mature brain are not fully understood, but are currently the subject of intense research. In this review, we will discuss old and novel Notch targets and molecular mediators that contribute to Notch function in the mature brain and will summarize recent findings that explore the two facets of Notch signaling in brain physiology and pathology.

Swiss tree rings reveal warm and wet summers during medieval times

We present a 1200 year drought reconstruction for the European Alpine region based on carbon isotope variations of tree rings from living larch trees and historic timber. The carbon isotope fractionation at the study site is sensitive to summer precipitation, temperature, and irradiance, resulting in a stable and high correlation with a drought index for interannual to decadal frequencies and possibly beyond (r(2)=0.58 for 1901-2004, July/August). When combining this information with maximum latewood density-derived summer temperature, a strongly reduced occurrence of summer droughts during the warm A.D. 900-1200 period is evident, coinciding with the Medieval Climate Anomaly (MCA), with a shift to colder and drier conditions for the subsequent centuries. The warm-wet MCA contrasts strongly with the climate of the drought-prone warm phase of the recent decades, indicating different forcing mechanism for these two warm periods and pointing to beneficial conditions for agriculture and human well-being during the MCA in this region.