Electron spin resonance on a 2-dimensional electron gas in a single AlAs quantum well

Direct electron spin resonance (ESR) on a high mobility two dimensional electron gas in a single AlAs quantum well reveals an electronic $g$-factor of 1.991 at 9.35 GHz and 1.989 at 34 GHz with a minimum linewidth of 7 Gauss. The ESR amplitude and its temperature dependence suggest that the signal originates from the effective magnetic field caused by the spin orbit-interaction and a modulation of the electron wavevector caused by the microwave electric field. This contrasts markedly to conventional ESR that detects through the microwave magnetic field.Comment: 4 pages, 4 figure

Endpoints of hepatitis B treatment

The goal of hepatitis B treatment is to prevent the development of cirrhosis, liver failure, and hepatocellular carcinoma. Ideally, clinical studies should demonstrate that hepatitis B therapies can prevent liver-related complications; however, these clinical endpoints evolve over years or decades. Therefore, clinical trials have relied on intermediate endpoints to evaluate the efficacy of treatment and to determine when treatment can be stopped. Intermediate endpoints that have been used include biochemical, histological, virological, and serological endpoints. This review will discuss the validity of these intermediate endpoints as surrogates of clinical endpoints, and the rates at which these intermediate endpoints can be achieved with currently available therapies.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79271/1/j.1365-2893.2010.01369.x.pd

Mississippi River Road Gabion Wall/Slope Stabilization

Lee County widened Mississippi River Road north of the Keokuk, Iowa in the early 1990s, removing material from the toe of slopes along the alignment. Gabion walls were constructed to provide grade separation. Significant precipitation occurred in the spring of 2010, and two (2) wall sections (about 100 feet each in length) failed. Based on our site exploration and instrumentation monitoring data, the gabion wall sections appeared to fail due to additional lateral load from a soil mass sliding on top of the shale bedrock and a buildup of high ground water levels. To support the additional load of the soil mass, reestablish the gabion wall/slope, and to keep the road open to traffic, a tied back, closely-spaced drilled shaft wall was designed to remediate the slide and augment the original gabion wall. This paper describes the investigation, analyses and the design and construction of the remedial measures adopted

Coulomb Drag as a Probe of the Nature of Compressible States in a Magnetic Field

Magneto-drag reveals the nature of compressible states and the underlying interplay of disorder and interactions. At \nu=3/2 a clear T^{4/3} dependence is observed, which signifies the metallic nature of the N=0 Landau level. In contrast, drag in higher Landau levels reveals an additional contribution, which anomalously grows with decreasing T before turning to zero following a thermal activation law. The anomalous drag is discussed in terms of electron-hole asymmetry arising from disorder and localization, and the crossover to normal drag at high fields as due to screening of disorder.Comment: 5 pages, 4 figure

Interventions to increase the uptake of seasonal influenza vaccination among pregnant women: A systematic review

© 2015 Elsevier Ltd.Background: Pregnant women and their infants under 6 months of age infected with influenza have a high risk of serious morbidity and mortality. Influenza vaccine during pregnancy offers 3-for-1 benefits to pregnant women, fetuses and newborn infants. Current vaccination uptake rates during pregnancy, however, are often lower than other high-risk groups and the general population. Methods: We systematically reviewed evidence on the effectiveness of interventions to improve influenza vaccination coverage in pregnant women. Risk differences (RDs) were calculated from the included studies. Results: Eleven studies were included in the review, of which four were randomized controlled trials (RCTs). Three cohort studies assessed provider-focused interventions while four RCTs and one cohort study evaluated pregnant women-focused interventions. Two cohort studies and a prospective intervention study assessed the effectiveness of bundled interventions. No study solely assessed the effectiveness of interventions to enhance access to influenza vaccination. One moderate quality RCT showed that an influenza pamphlet, with or without a verbalized benefit statement, improved the vaccination rate (RD. =0.26; RD. =0.39). The other reviewed RCTs showed discordant results, with RDs ranging from -0.15 to 0.03. Although all observational studies significantly improved vaccination rates (RDs ranged from 0.03 to 0.44), the quality of the evidence varied. Conclusions: There is a lack of effective interventions to increase the influenza vaccination rate in pregnant women. Based on the existing research, we recommend that clinicians provide influenza pamphlets to pregnant women with a verbalized statement about the benefits of influenza vaccine to newborns. Further high-quality RCTs are needed to develop successful maternal influenza vaccination programs. Increased clarity in reporting the content of interventions would help to improve the comparability and generalizability of the published studies.postprin

Activated Transport in the individual Layers that form the νT\nu_T=1 Exciton Condensate

We observe the total filling factor $\nu_{T}$=1 quantum Hall state in a bilayer two-dimensional electron system with virtually no tunnelling. We find thermally activated transport in the balanced system with a monotonic increase of the activation energy with decreasing $d/\ell_B$ below 1.65. In the imbalanced system we find activated transport in each of the layers separately, yet the activation energies show a striking asymmetry around the balance point. This implies that the gap to charge-excitations in the {\em individual} layers is substantially different for positive and negative imbalance.Comment: 4 pages. 4 figure

PEPPER : persistent ear problems, providing evidence for referral

This PhD research describes the first steps to develop an instrument for children with glue ears (otitis media) and impaired hearing, who need referral and perhaps treatment with tympanotomy tubes. For this purpose a questionnaire is used with risk factors for glue ears (the existing PEPPER questionnaire, 'Persistent Ear Problems, Providing Evidence for Referral'). A score form has been developed that predicts on the basis of a model with ten risk factors which children in the PEPPER study have been treated with tubes. The score form seems promising, but further research will have to investigate among others the practical usability

Exciton condensate at a total filling factor of 1 in Corbino 2D electron bilayers

Magneto-transport and drag measurements on a quasi-Corbino 2D electron bilayer at the systems total filling factor 1 (v_tot=1) reveal a drag voltage that is equal in magnitude to the drive voltage as soon as the two layers begin to form the expected v_tot=1 exciton condensate. The identity of both voltages remains present even at elevated temperatures of 0.25 K. The conductance in the current carrying layer vanishes only in the limit of strong coupling between the two layers and at T->0 K which suggests the presence of an excitonic circular current

Micro-SQUID technique for studying the temperature dependence of switching fields of single nanoparticles

An improved micro-SQUID technique is presented allowing us to measure the temperature dependence of the magnetisation switching fields of single nanoparticles well above the critical superconducting temperature of the SQUID. Our first measurements on 3 nm cobalt nanoparticle embedded in a niobium matrix are compared to the Neel Brown model describing the magnetisation reversal by thermal activation over a single anisotropy barrier.Comment: 3 pages, 4 figures; conference proceeding: 1st Joint European Magnetic Symposia (JEMS'01), Grenoble (France), 28th August - 1st September, 200