Statistical Basics of a Reliable World Wide Web Peer to Peer Storage System

Peer-to-peer networks are highly distributed and unreliable networks. Peers log in and off the network at their own needs without any overall plan. In the real peer-to-peer case there are no central nodes planning the resources of the network or having an overview about the state of the network. The paper on hand describes and mathematically analyzes a storage algorithm allowing information to be stored within the network without the originator of the information needs to stay online. Information is optimally “blurred” within the network meaning that the information is reconstructable with a high probability and a long time interval, but stored as least redundant as possible. The main focus is to analyze the mathematical and statistical properties of the presented peer-to-peer storage algorithm. Technical procedures are described at a high level and need further improvement. Thus, the paper on hand is primarily purely statistically peer-to-peer theory at this stage of research

A peer-to-peer network to support scholarly communication

The number of scientific journals and thereby the number of published articles grew with an enormous rate in the last century (e.g. Price 1986; Henderson 2002). In the second half of the 20th century the system seemed to abut against its boundaries, because in relation to research budgets, library budgets did not grow fast enough to cover all the scientific output produced. Price increases well above the inflation rate set by commercial publishers that bundle disproportionately high market power – especially for journals in the Science-Technical- Medicine-Sector in the last thirty years – intensified the situation even further. This situation is known as the serial crisis. New Information and Communication Technology (ICT) driven publication models are established and seem to be a promising way out of the crisis because they reduce distribution costs significantly. Especially the open access (OA) movement that advocates free electronic access to scientific output is subject to a fierce public debate. In this paper we will detail problems associated with OA and suggest a Peer-to-Peer (P2P) system that supports electronic scholarly communication as a tool to address the economic problems mentioned above

A cross-disciplinary approach to understanding neural stem cells in development and disease

© 2010. Published by The Company of Biologists LtdThe Company of Biologists recently launched a new series of workshops aimed at bringing together scientists with different backgrounds to discuss cutting edge research in emerging and cross-disciplinary areas of biology. The first workshop was held at Wilton Park, Sussex, UK, and the chosen theme was ‘Neural Stem Cells in Development and Disease’, which is indeed a hot topic, not only because of the potential use of neural stem cells in cell replacement therapies to treat neurodegenerative diseases, but also because alterations in their behaviour can, in certain cases, lie at the origin of brain tumours and other diseases.Work in D.H.’s laboratory is supported by Fundação Ciência e Tecnologia and Fundação Champalimaud Neuroscience Program. Work in L.B.-C’s laboratory is supported by the CNRS, the French National Research Agency (ANR), the Medical Research Foundation (FRM), the Paris School of Neuroscience (ENP), the PIME program, the Schlumberger Association for Education and Research (FSER), and the European 7th Framework Program (IP NeuroXsys)

Sea-level rise in Denmark: paleo context, recent projections and policy implications

We present the most recent Intergovernmental Panel on Climate Change Sixth Assessment Report (AR6) sea-level projections for four Danish cities (Aarhus, Copenhagen, Esbjerg and Hirtshals) under the Shared Socioeconomic Pathway (SSP) family of climate scenarios. These sea-level changes projected over the next century are up to an order of magnitude larger than those observed over the previous century. At these cities, year 2150 sea-level changes of between 29 and 55 cm are projected under the very low emissions scenario (SSP1-1.9), while changes of between 99 and 123 cm are projected under the very high emissions scenario (SSP5-8.5). These differences highlight the potentially significant impact of remaining opportunities for climate change mitigation. Due to this increase in mean sea level, the mean recurrence time between historically extreme events is expected to decrease. Under the very high emissions scenario, the historical 100-year storm flood event will become a 1- to 5-year event at most Danish harbours by 2100. There is considerable uncertainty associated with these sea-level projections, primarily driven by uncertainty in the future evolution of the Antarctic ice sheet and future sterodynamic changes in ocean volume. The AR6 characterises collapse of the West Antarctic ice sheet as a low-probability but high-impact event that could cause several metres of sea-level rise around Denmark by 2150. In climate adaptation policy, the scientific landscape is shifting fast. There has been a tremendous proliferation of diverse sea-level projections in recent years, with the most relevant planning target for Denmark increasing c. 50 cm in the past two decades. Translating sea-level rise projections into planning targets requires value judgments about acceptable sea-level risk that depend on local geography, planning timeline and climate pathway. This highlights the need for an overarching national sea-level adaptation plan to ensure municipal plans conform to risk and action standards

An optimised assay for quantitative, high-throughput analysis of polysialyltransferase activity

YesThe polysialyltransferases are biologically important glycosyltransferase enzymes responsible for the biosynthesis of polysialic acid, a carbohydrate polymer that plays a critical role in the progression of several diseases, notably cancer. Having improved the chemical synthesis and purification of the fluorescently-labelled DMB-DP3 acceptor, we report optimisation and validation of a highly sensitive cell-free high-throughput HPLC-based assay for assessment of human polysialyltransferase activity

Absence of polysialylated NCAM is an unfavorable prognostic phenotype for advanced stage neuroblastoma

<p>Abstract</p> <p>Background</p> <p>The expression of a neural crest stem cell marker, polysialic acid (polySia), and its main carrier, neural cell adhesion molecule (NCAM), have been detected in some malignant tumors with high metastatic activity and unfavorable prognosis, but the diagnostic and prognostic value of polySia-NCAM in neuroblastoma is unclear.</p> <p>Methods</p> <p>A tumor tissue microarray (TMA) of 36 paraffin-embedded neuroblastoma samples was utilized to detect polySia-NCAM expression with a polySia-binding fluorescent fusion protein, and polySia-NCAM expression was compared with clinical stage, age, <it>MYCN </it>amplification status, histology (INPC), and proliferation index (PI).</p> <p>Results</p> <p>PolySia-NCAM-positive neuroblastoma patients had more often metastases at diagnosis, and polySia-NCAM expression associated with advanced disease (<it>P </it>= 0.047). Most interestingly, absence of polySia-NCAM-expressing tumor cells in TMA samples, however, was a strong unfavorable prognostic factor for overall survival in advanced disease (<it>P </it>= 0.0004), especially when <it>MYCN </it>was not amplified. PolySia-NCAM-expressing bone marrow metastases were easily detected in smears, aspirates and biopsies.</p> <p>Conclusion</p> <p>PolySia-NCAM appears to be a new clinically significant molecular marker in neuroblastoma, hopefully with additional value in neuroblastoma risk stratification.</p