Degradation and breakdown characteristics of thin MgO dielectric layers

MgO has been suggested as a possible high-k dielectric for future complementary metal-oxide semiconductor processes. In this work, the time dependent dielectric breakdown (TDDB) characteristics of 20 nm MgO films are discussed. Stress induced leakage current measurements indicate that the low measured Weibull slopes of the TDDB distributions for both n-type and p-type devices cannot be attributed to a lower trap generation rate than for SiO2. This suggests that much fewer defects are required to trigger breakdown in MgO under voltage stress than is the case for SiO2 or other metal-oxide dielectrics. This in turn explains the progressive nature of the breakdown in these films which is observed both in this work and elsewhere. The reason fewer defects are required is attributed to the morphology of the films

Transcriptional networks specifying homeostatic and inflammatory programs of gene expression in human aortic endothelial cells.

Endothelial cells (ECs) are critical determinants of vascular homeostasis and inflammation, but transcriptional mechanisms specifying their identities and functional states remain poorly understood. Here, we report a genome-wide assessment of regulatory landscapes of primary human aortic endothelial cells (HAECs) under basal and activated conditions, enabling inference of transcription factor networks that direct homeostatic and pro-inflammatory programs. We demonstrate that 43% of detected enhancers are EC-specific and contain SNPs associated to cardiovascular disease and hypertension. We provide evidence that AP1, ETS, and GATA transcription factors play key roles in HAEC transcription by co-binding enhancers associated with EC-specific genes. We further demonstrate that exposure of HAECs to oxidized phospholipids or pro-inflammatory cytokines results in signal-specific alterations in enhancer landscapes and associate with coordinated binding of CEBPD, IRF1, and NFκB. Collectively, these findings identify cis-regulatory elements and corresponding trans-acting factors that contribute to EC identity and their specific responses to pro-inflammatory stimuli

Teach Them How They Learn: Learning Styles and Information Systems Education

The rich, interdisciplinary tradition of learning styles is markedly absent in information systems-related research. The current study applies the framework of learning styles to a common educational component of many of today’s information systems curricula - object-oriented systems development - in an effort to answer the question as to whether one’s learning style, when matched with a specific complementary instructional methodology, results in increased domain-specific performance. The data collected from 196 information systems majors enrolled in object-oriented systems development courses suggest that task performances increases significantly when the instructional methodology closely mirrors the student’s learning style inclination

Infrared colours and inferred masses of metal-poor giant stars in the Keplerfield

Intrinsically luminous giant stars in the Milky Way are the only potential volume-complete tracers of the distant disk, bulge, and halo. The chemical abundances of metal-poor giants also reflect the compositions of the earliest star-forming regions, providing the initial conditions for the chemical evolution of the Galaxy. However, the intrinsic rarity of metal-poor giants combined with the difficulty of efficiently identifying them with broad-band optical photometry has made it difficult to exploit them for studies of the Milky Way. One long-standing problem is that photometric selections for giant and/or metal-poor stars frequently include a large fraction of metal-rich dwarf contaminants. We re-derive a giant star photometric selection using existing public g-band and narrow-band DDO51photometry obtained in the Keplerfield. Our selection is simple and yields a contamination rate of main-sequence stars of ≲1% and a completeness of about 80 % for giant stars with Teff ≲ 5250 K - subject to the selection function of the spectroscopic surveys used to estimate these rates, and the magnitude range considered (11 ≲ g ≲ 15). While the DDO51filter is known to be sensitive to stellar surface gravity, we further show that the mid-infrared colours of DDO51-selected giants are strongly correlated with spectroscopic metallicity. This extends the infrared metal-poor selection developed by Schlaufman & Casey, demonstrating that the principal contaminants in their selection can be efficiently removed by the photometric separation of dwarfs and giants. This implies that any similarly efficient dwarf/giant discriminant (e.g., Gaiaparallaxes) can be used in conjunction with WISEcolours to select samples of giant stars with high completeness and low contamination. We employ our photometric selection to identify three metal-poor giant candidates in the Keplerfield with global asteroseismic parameters and find that masses inferred for these three stars using standard asteroseismic scaling relations are systematically over-estimated by 20-175%. Taken at face value, this small sample size implies that standard asteroseismic scaling relations over-predict stellar masses for metal-poor giant stars

Clinical experience with Timentin in severe hospital infections

Sixty-four severe infections in hospitalized patients were treated with intravenous Timentin. Most patients (mean age: 50-5 years, range 18-85) had serious underlying conditions such as agranulocytosis, heart failure, cancer, diabetes mellitus, chronic alcoholism or other functional or anatomical abnormalities. Forty-three episodes were bacteriologically proved, and bacteraemia was diagnosed in 18. The sites of infection were: lower respiratory tract (10), upper respiratory tract (10), soft tissues(9), urinary tract (7), bones (6), peritoneal cavity (3), meninges (1) and pelvis (1). Inaddition, 13 episodes of fever and four of septicaemia in patients with agranulocytosis were treated with Timentin plus amilcacin. Overall, 59% of the episodes were cured, 14% improved and 17% failed to respond. In 9% of cases the efficacy of the Timentin was unassessable mainly because of concurrent administration of other antimicrobials. Failure appeared to be more frequent in soft tissue and intra-abdominal infections, in patients infected with bacteria susceptibleto Timentin but resistant to ticarcillin and in patients superinfected with Timentin-resistant strains. Major side effects were haemorrhagic diathesis with platelet dysfunction (1), severe water sodium overload (1), and possibly pancreatitis (1).Other side effects were mild: catheter-related phlebitis, and abnormal but clinically insignificant laboratory test results. Timentin appears to be an effective and safebroad-spectrum combination which compares favourably with third-generation cephalosporins in the treatment of severe hospital infections. More experience is needed to decide whether the some what lower response rate in patients infected with ticarcillin-resistant strains is significan