Crossover from Kondo assisted suppression to co-tunneling enhancement of tunneling magnetoresistance via ferromagnetic nanodots in MgO tunnel barriers

Recently, it has been shown that magnetic tunnel junctions with thin MgO tunnel barriers exhibit extraordinarily high tunneling magnetoresistance (TMR) values at room temperature1, 2. However, the physics of spin dependent tunneling through MgO barriers is only beginning to be unravelled. Using planar magnetic tunnel junctions in which ultra-thin layers of magnetic metals are deposited in the middle of a MgO tunnel barrier here we demonstrate that the TMR is strongly modified when these layers are discontinuous and composed of small pancake shaped nanodots. At low temperatures, in the Coulomb blockade regime, for layers less than ~1 nm thick, the conductance of the junction is increased at low bias consistent with Kondo assisted tunneling. In the same regime we observe a suppression of the TMR. For slightly thicker layers, and correspondingly larger nanodots, the TMR is enhanced at low bias, consistent with co-tunneling.Comment: Nano Letters (in press

The Evolution of Abdominal Compression in Cardiopulmonary Resuscitation

Objective: To review the history of external abdominal compression as an adjunct to cardiopulmonary resuscitation (CPR), tracking the development of five major themes over the course of the 20th century: 1) augmentation of peripheral resistance by physical means, 2) risk of hepatic injury with abdominal compression, 3) counterpulsation vs. sustained compression, 4) the abdominal pump mechanism, and 5) contact compression techniques. Methods: Literature retrieved from successive MEDLINE English-language searches was reviewed with a special emphasis on work and concepts highlighted by participants at the First Purdue Conference on Interposed Abdominal Compression-CPR, September 1992. Results: External abdominal compression of one form or another has been studied as a means of resuscitation by many investigators throughout the 20th century. Experimental and clinical studies have shown generally consistent evidence of hemodynamic augmentation by abdominal compression during various forms of CPR. Recent advances include a modified theoretical understanding of hemodynamic mechanisms and demonstration of clinical potential in humans. Inconsistencies in published results may be due to differences in mechanical techniques of abdominal compression. Based on these studies, a modified manual technique for contact compression of the abdominal aorta is recommended. Conclusions: A technique for left-of-center, angled compression of the abdominal aorta against the crest of the spine is recommended. Further well-supervised and controlled clinical trials using this standardized technique are warranted as a prelude to more widespread clinical application of abdominal compression in CPR

Prospective observational cohort study of oesophagogastric cancer patients (POCOP): A Dutch nationwide cohort

Experimentele farmacotherapi

New values of time and reliability in passenger transport in The Netherlands

We have established new values of time (VOTs) and values of travel time reliability (VORs) for use in cost-benefit analysis (CBA) of transport projects in The Netherlands. This was the first national study in The Netherlands (and one of the first world-wide) to investigate these topics empirically in a joint framework. Stated preference (SP) questionnaires were designed for interviewing travellers, where the hypothetical alternatives were described in terms of travel time, travel costs and travel time reliability, the latter being presented to the respondents in the form of five possible travel times having equal probability. For passenger transport, we first collected interviews using an existing internet panel. Additional data collection recruitment was done by asking travellers at petrol stations/service areas, parking garages, stations, bus stops, airports and ports to participate in the survey. One important conclusion is that the SP survey using members of this internet panel leads to substantially lower VOTs than the SP survey with en-route recruitment, probably because of self-selection bias in the internet panel. We estimated discrete choice models in which the values of time differ between trips with different time and costs levels, different time and costs changes offered in the SP, and different observed characteristics of the respondents (e.g. education, income, age, household composition). By using a panel latent class model, we also account for unobserved differences between respondents in the value of time and for repeated measurements/panel effects. The reference values of time and the reference reliability ratios were estimated on the 2011 sample only, but the effect of time and cost level, time and cost changes offered and socio-economic attributes was estimated on both the 2009 and 2011 samples

Beyond the Hype: e-business strategy in leading European companies

In this examination of the current state of business technology, two successful e-businessmen combine interviews of 20 captains of European industry regarding their visions of the future of e-business with their own insights, providing inside information on Internet hype as well as ideas for future strategies. Topics covered include e-governance, new economy valuation, budgeting, and innovation strategy. A discussion of the business world's initial responses in the aftermath of the events of September 11 is also included

Beyond the Hype:e-business strategy in leading European companies

In this examination of the current state of business technology, two successful e-businessmen combine interviews of 20 captains of European industry regarding their visions of the future of e-business with their own insights, providing inside information on Internet hype as well as ideas for future strategies. Topics covered include e-governance, new economy valuation, budgeting, and innovation strategy. A discussion of the business world's initial responses in the aftermath of the events of September 11 is also included

Connected Future; E-business in balans

In het begin van deze rede schetsen we aan de hand van voorbeelden het individuele, het business en het maatschappelijk perspectief van Internet. We laten zien hoe ver Internet al is doorgedrongen in ons privé en in ons openbare leven. In bijna alle maatschappelijke rollen die u speelt komt u inmiddels Internet tegen. Dat is spannend. Dan ontstaat er dus een nieuw evolutionair proces waarin de meest aangepaste aan Internet en E-business maximaal profiteert. Dat geldt voor individuen, organisaties en wellicht ook hele landen. Waar we het met u over willen hebben is waaraan we ons dan moeten aanpassen. Wat doet Internet met ons, met ons bedrijf, met ons gezin, onze baan, met Nederland? Waar heeft Internet een rol en waar per se niet

Supercurrent Interference in Few-Mode Nanowire Josephson Junctions

International audienceJunctions created by coupling two superconductors via a semiconductor nanowire in the presence of high magnetic fields are the basis for the potential detection, fusion, and braiding of Majorana bound states. We study NbTiN = InSb nanowire = NbTiN Josephson junctions and find that the dependence of the critical current on the magnetic field exhibits gate-tunable nodes. This is in contrast with a well-known Fraunhofer effect, under which critical current nodes form a regular pattern with a period fixed by the junction area. Based on a realistic numerical model we conclude that the Zeeman effect induced by the magnetic field and the spin-orbit interaction in the nanowire are insufficient to explain the observed evolution of the Josephson effect. We find the interference between the few occupied one-dimensional modes in the nanowire to be the dominant mechanism responsible for the critical current behavior. We also report a strong suppression of critical currents at finite magnetic fields that should be taken into account when designing circuits based on Majorana bound state