Researchers’ opinions about ethically sound dissemination of BCI research to the public media

BCI research and (future) applications raise ethical questions. A websurvey among 144 BCI researchers identified disseminating BCI research to the public media as a central topic. Most researchers felt that BCI scientists must responsibly communicate with the media and that general ethical guidelines on BCI research and application are needed within the next 5 years. We recommend further debate on ethical aspects related to BCI and the development of guidelines

Across cultures:The introduction of iron in the western Mediterranean, 10th and 9th centuries BC

The transition from Bronze to Iron Age in the western Mediterranean during the 10th and 9th centuries BC is based on the awareness of the inherent advantages of the metal iron over copper-alloys when it comes to two contrary attributes, hardness and malleability. Both qualities of iron/steel could and were manipulated during smelting of the iron-ores and the subsequent smiting. It created perfect implements of all kinds, most of which can nowadays still be bought in hardware stores. The paper examines the structural, generic introduction of this novel metal in mainly Italy and Spain/Portugal. It presents well-published sites where relatively much early iron was excavated in combination with related radiocarbon dates. It turns out that the intrinsic qualities of iron are appreciated mainly in iron/steel knives from the 10th century BC onwards after which the repertoire of iron tools and weapons rapidly enlarged till it became the prevailing metal for all tools and weapons in a couple of centuries. The technological transfer involved, appears related to the Phoenicians, who crossed the whole Mediterranean from the 11th – 10th century BC onwards, well before the establishment of permanent overseas settlements. Local overland networks on the Italian Peninsula and in the southern part of the Iberian Peninsula resulted in the distribution of the early iron artefacts. In Italy the accompanying technological know-how seems to have spread along these landlocked arteries as well.Another benefit in this transition from bronze to iron is the availability of terrestrial metal-ores; iron-ores are far more ubiquitous than copper- and tin-ores necessary for the manufacture of bronze. Therefore, the growing use of iron as a base-metal and the local/regional exploitation of iron-ores inevitably resulted in its devaluation. This process of deflation is best recorded in the Near and Middle East from onward the 11th – 10th centuries BC. However, it must successively have occurred in the western Mediterranean, especially during the 8th century BC and later. These intricate topics concerning the introduction of iron are described with moderation since the associated archaeological data for the 10th and 9th century BC are improving but still remain somewhat patchy.<br/

Spin injection and spin accumulation in permalloy-copper mesoscopic spin valves

We study the electrical injection and detection of spin currents in a lateral spin valve device, using permalloy (Py) as ferromagnetic injecting and detecting electrodes and copper (Cu) as non-magnetic metal. Our multi-terminal geometry allows us to experimentally distinguish different magneto resistance signals, being 1) the spin valve effect, 2) the anomalous magneto resistance (AMR) effect and 3) Hall effects. We find that the AMR contribution of the Py contacts can be much bigger than the amplitude of the spin valve effect, making it impossible to observe the spin valve effect in a 'conventional' measurement geometry. However, these 'contact' magneto resistance signals can be used to monitor the magnetization reversal process, making it possible to determine the magnetic switching fields of the Py contacts of the spin valve device. In a 'non local' spin valve measurement we are able to completely isolate the spin valve signal and observe clear spin accumulation signals at T=4.2 K as well as at room temperature. We obtain spin diffusion lengths in copper of 1 micrometer and 350 nm at T=4.2 K and room temperature respectively.Comment: 8 pages (incl. figures), 7 figures, RevTex, conferenc

The Critical Aggregation Concentration of ß-Lactoglobulin-Based Fibril Formation

The critical aggregation concentration (CAC) for fibril formation of ß-lactoglobulin (ß-lg) at pH 2 was determined at 343, 353, 358, 363, and 383 K using a Thioflavin T assay and was approximately 0.16 wt%. The accuracy of the CAC was increased by measuring the conversion into fibrils at different stirring speeds. The corresponding binding energy per mol, as determined from the CAC, was 13 RT (~40 kJ mol¿1) for the measured temperature range. The fact that the CAC was independent of temperature within the experimental error indicates that the fibril formation of ß-lg at pH 2 and the measured temperature range is an entropy-driven process

Calibration Challenges for Future Radio Telescopes

Instruments for radio astronomical observations have come a long way. While the first telescopes were based on very large dishes and 2-antenna interferometers, current instruments consist of dozens of steerable dishes, whereas future instruments will be even larger distributed sensor arrays with a hierarchy of phased array elements. For such arrays to provide meaningful output (images), accurate calibration is of critical importance. Calibration must solve for the unknown antenna gains and phases, as well as the unknown atmospheric and ionospheric disturbances. Future telescopes will have a large number of elements and a large field of view. In this case the parameters are strongly direction dependent, resulting in a large number of unknown parameters even if appropriately constrained physical or phenomenological descriptions are used. This makes calibration a daunting parameter estimation task, that is reviewed from a signal processing perspective in this article.Comment: 12 pages, 7 figures, 20 subfigures The title quoted in the meta-data is the title after release / final editing

The Painting Industries of Antwerp and Amsterdam, 1500−1700: A Data Perspective

This study presents a data driven comparative analysis of the painting industries in sixteenth and seventeenth century Antwerp and Amsterdam. The popular view of the development of these two artistic centers still holds that Antwerp flourished in the sixteenth century and was succeeded by Amsterdam after the former&rsquo;s recapturing by the Spanish in 1585. However, a demographic analysis of the number of painters active in Antwerp and Amsterdam shows that Antwerp recovered relatively quickly after 1585 and that it remained the leading artistic center in the Low Countries, only to be surpassed by Amsterdam in the 1650&rsquo;s. An analysis of migration patterns and social networks shows that painters in Antwerp formed a more cohesive group than painters in Amsterdam. As a result, the two cities responded quite differently to internal and external market shocks. Data for this study are taken from ECARTICO, a database and a linked data web resource containing structured biographical data on over 9100 painters working in the Low Countries until circa 1725