All Optical Implementation of Multi-Spin Entanglement in a Semiconductor Quantum Well

We use ultrafast optical pulses and coherent techniques to create spin entangled states of non-interacting electrons bound to donors (at least three) and at least two Mn2+ ions in a CdTe quantum well. Our method, relying on the exchange interaction between localized excitons and paramagnetic impurities, can in principle be applied to entangle a large number of spins.Comment: 17 pages, 3 figure

The Rotterdam Study: 2012 objectives and design update

The Rotterdam Study is a prospective cohort study ongoing since 1990 in the city of Rotterdam in The Netherlands. The study targets cardiovascular, endocrine, hepatic, neurological, ophthalmic, psychiatric, dermatological, oncological, and respiratory diseases. As of 2008, 14,926 subjects aged 45 years or over comprise the Rotterdam Study cohort. The findings of the Rotterdam Study have been presented in over a 1,000 research articles and reports (see www.erasmus-epidemiology.nl/rotterdamstudy). This article gives the rationale of the study and its design. It also presents a summary of the major findings and an update of the objectives and methods

Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

LOCAL MODES OF SUBSTITUTIONAL TRANSITION-METAL IONS IN II-VI SEMICONDUCTORS

The 3d transition metal ions (TMI) substituting for the cations in the tetrahedrally coordinated zincblende II-VI semiconductors display a localized mode above the rest-strahlen when introduced in dilute concentrations. The local mode observed in the infrared exhibits a characteristic dependence on the isotopic mass of the TMI. In the wurtzite II-VIs, the local mode undergoes a splitting into two components, one polarized along the optic axis and the other normal to it. The local mode frequency shows a striking non-monotonic dependence on the number of 3d electrons of the TMI

Local and gap modes of substitutional 3d transition-metal ions in zinc-blende and wurtzite II-VI semiconductors

The localized vibrational modes of the 3d transition-metal ions (TMI's) substituting for the cations in CdTe, ZnTe, and CdSe appear in infrared absorption with as many lines as there are isotopes of the impurity and with intensities proportional to their natural abundances. The triply degenerate local mode in a zinc-blende host splits into a singlet and a doublet in a wurtzite host, the former appearing only when the electric vector (E) of the incident radiation is parallel to the optic axis ((c) over cap) and the latter when . Replacement of Cd by a TMI in CdSe results in high-frequency local vibrational as well as gap modes lying in the gap between the acoustic- and optic-phonon branches, the latter exhibiting an optical anistropy similar to that of the former. Both the local and the gap modes exhibit a unique nonmonotonic trend across the 3d transition-metal series, with a minimum at Mn

Observation of quasibound states in semiconductor single quantum barriers

We report the observation of quasibound states in single semiconductor barriers, in heterostructures with both type-I and type-II band alignments. We disucss the localization and the shape of wave functions of such states, as well as their density of states. In structures with type-II band alignment (CdSeZnTe and CdMnSe/ZnTe) we observe transitions involving electrons confined in the conduction band well and quasibound holes localized in the valence band barrier (both in the CdSe layer). In the system with type-I band alignment (ZnMnSe/ZnSe) transitions between states quasibound in the single ZnMnSe barrier also show clear absorption peaks. © 1993 The American Physical Society.link_to_subscribed_fulltex