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High flavonoid consumption can improve vascular health. Exploring flavonoid–metabolome relationships in population-based settings is challenging, as: (i) there are numerous confounders of the flavonoid–metabolome relationship; and (ii) the set of dependent metabolite variables are inter-related, highly variable and multidimensional. The Metabolite Fingerprint Score has been developed as a means of approaching such data. This study aims to compare its performance with that of more traditional methods, in identifying the metabolomic fingerprint of high and low flavonoid consumers. This study did not aim to identify biomarkers of intake, but rather to explore how systemic metabolism differs in high and low flavonoid consumers. Using liquid chromatography–tandem MS, 174 circulating plasma metabolites were profiled in 584 men and women who had complete flavonoid intake assessment. Participants were randomised to one of two datasets: (a) training dataset, to determine the models for the discrimination variables (n 399); and (b) validation dataset, to test the capacity of the variables to differentiate higher from lower total flavonoid consumers (n 185). The stepwise and full canonical variables did not discriminate in the validation dataset. The Metabolite Fingerprint Score successfully identified a unique pattern of metabolites that discriminated high from low flavonoid consumers in the validation dataset in a multivariate-adjusted setting, and provides insight into the relationship of flavonoids with systemic lipid metabolism. Given increasing use of metabolomics data in dietary association studies, and the difficulty in validating findings using untargeted metabolomics, this paper is of timely importance to the field of nutrition. However, further validation studies are required.
Radio-glaciological parameters from the Moore’s Bay region of the Ross Ice Shelf, Antarctica, have been measured. The thickness of the ice shelf in Moore’s Bay was measured from reflection times of radio-frequency pulses propagating vertically through the shelf and reflecting from the ocean, and is found to be 576 ± 8 m. Introducing a baseline of 543 ± 7m between radio transmitter and receiver allowed the computation of the basal reflection coefficient, R, separately from englacial loss. The depth-averaged attenuation length of the ice column, 〈L〉 is shown to depend linearly on frequency. The best fit (95% confidence level) is 〈L(ν)〉= (460±20) − (180±40)ν m (20 dB km−1), for the frequencies ν = [0.100–0.850] GHz, assuming no reflection loss. The mean electric-field reflection coefficient is (1.7 dB reflection loss) across [0.100–0.850] GHz, and is used to correct the attenuation length. Finally, the reflected power rotated into the orthogonal antenna polarization is <5% below 0.400 GHz, compatible with air propagation. The results imply that Moore’s Bay serves as an appropriate medium for the ARIANNA high-energy neutrino detector.
Numerous factors are thought to be advantageous for non-native language learning although they are typically investigated in isolation, and the interaction between them is not understood. Firstly, bilinguals are claimed to acquire a third language easier than monolinguals acquire a second. Secondly, closely related languages may be easier to learn. Thirdly, certain phonetic features could be universally more difficult to acquire. We tested these hypotheses used as explanations by having adults learn vocabularies that differentiated words using foreign phonetic contrasts. In Experiment 1, Mandarin–English bilinguals outlearned English monolinguals, and the Mandarin-like (retroflex) artificial language was better learned than the English-like (fricative voicing). In Experiment 2, bilinguals again outlearned English monolinguals for the Mandarin-like artificial language. However, only Korean–English bilinguals showed an advantage for the more difficult Korean-like (lenition) language. Bilinguals, relative to monolinguals, show a general advantage when learning ‘easy’ contrasts, but phonetic similarity to the native language is useful for learning universally ‘difficult’ contrasts.
The paper proposes a new design for a single-arm, rectangular, spiral antenna (SARSA) with a wide azimuth space coverage. The antenna, operating at around 3.3 GHz, is capable of steering the beam in four separate directions in the azimuth plane. Only three DC signals are required to control the seven PIN diodes attached along the spiral arm. The antenna has a 200-MHz-bandwidth around 3.3 GHz with stable maximum beam directions that are defined by setting of the switches. Considerations required in selecting switch positions when designing such antennas for other frequencies, are presented. The measured return loss, radiation pattern and gain, all have close correlation with the simulation results. A detailed comparison of our design with those already proposed in the literature is given.
As traditional poly-silicon gated MOSFET devices scale, the additional series capacitance due to poly-silicon depletion becomes an increasingly large fraction of the total gate capacitance, excessive boron penetration causes threshold voltage shifts, and the gate resistance is elevated. To solve these problems and continue aggressive device scaling we are studying metal electrodes with suitable work-functions and sufficient physical and electrical stability. Our studies of metal gates on HfO2 indicate that excessive inter-diffusion, inadequate phase stability, and interfacial reactions are mechanisms of failure at source drain activation temperatures that must be considered during the electrode selection process. Understanding the physical properties of the metal gate – HfO2 interface is critical to understanding the electrical behavior of MOS devices. Of particular interest is Fermi level pinning, a phenomenon that occurs at metal – dielectric interfaces which causes undesirable shifts in the effective metal work function. The magnitude of Fermi level pinning on HfO2 electrodes is studied with Pt and LaB6 electrodes. In addition, the intrinsic and extrinsic contributions to Fermi level pinning of platinum electrodes on HfO2 gate dielectrics are investigated by examining the impact of oxygen and forming gas anneals on the work function of platinum-HfO2-silicon capacitors. The presence of interfacial oxygen vacancies or Pt-Hf bonds is believed to be responsible for a degree of pinning that is stronger than predicted from the MIGS model alone. Interface chemistry and defects influence the effective metal work function.
Many snow models have been developed for various applications such as hydrology, global atmospheric circulation models and avalanche forecasting. The degree of complexity of these models is highly variable, ranging from simple index methods to multi-layer models that simulate snow-cover stratigraphy and texture. In the framework of the Snow Model Intercomparison Project (SnowMIP), 23 models were compared using observed meteorological parameters from two mountainous alpine sites. The analysis here focuses on validation of snow energy-budget simulations. Albedo and snow surface temperature observations allow identification of the more realistic simulations and quantification of errors for two components of the energy budget: the net short- and longwave radiation. In particular, the different albedo parameterizations are evaluated for different snowpack states (in winter and spring). Analysis of results during the melting period allows an investigation of the different ways of partitioning the energy fluxes and reveals the complex feedbacks which occur when simulating the snow energy budget. Particular attention is paid to the impact of model complexity on the energy-budget components. The model complexity has a major role for the net longwave radiation calculation, whereas the albedo parameterization is the most significant factor explaining the accuracy of the net shortwave radiation simulation.
Disaster is a collective responsibility requiring coordinated response from all parts of society. This theme focused on coordination and management issues in a diverse range of scenarios.
Details of the methods used are provided in the preceding paper. The chairs moderated all presentations and produced a summary that was presented to an assembly of all of the delegates. Although the main points developed in Themes 1 and 4 were different from each other (as reported in the Results section), their implementation was similar. Therefore, the chairs of both groups presided over one workshop that resulted in the generation of a set of Action Plans that then were reported to the collective group of all delegates.
The main points developed during the presentations and discussions included: (1) the need for evidence-based assessments and planning, (2) the need for a shift in focus to health-sector readiness, (3) empowerment of survivors, (4) provision of relief for the caregivers, (5) address the incentives and disincentives to attain readiness, (6) engage in joint preparation, response, and training, (7) focus on prevention and mitigation of the damage from events, and (8) improve media relations. There exists a need for institutionalization of processes for learning from experiences obtained from disasters.
Action plans presented include: (1) creation of an Information and Data Clearinghouse on Disaster Management, (2) identification of incentives and disincentives for readiness and develop strategies and interventions, and (3) act on lessons learned from evidence-based research and practical experience.
There is an urgent need to proactively establish coordination and management procedures in advance of any crisis. A number of important insights for improvement in coordination and management during disasters emerged.
We have systematically investigated the effect of H2 dilution on the stability of a-Si:H based solar cells. The results clearly show that the device stability against light soaking improves substantially with increasing H2 dilution until a threshold is reached. Beyond this threshold which depends on the substrate temperature, the stability no longer changes with further increase in H2 dilution. On the other hand, at a given ratio of H2 to the reactant gases, the device stability generally improves with increasing substrate temperature. Multi-step light soaking experiments have shown that devices made with H2 dilution saturate much faster (∼100 hours) under one-sun illumination and exhibit little overshoot effect in the recovery process, in sharp contrast to devices made without H2 dilution. Based on the simple two-component model for defect kinetics, these observations and the fact that the apparent saturation time coincides with the time constant of the “fast” defects strongly suggest that negligible amount of “slow” defects exist in materials made with H2 dilution. While H2 dilution generally suppresses the formation of microstructure giving rise to dihydride bonding and microvoids, the differences in the kinetics of light induced degradation cannot always be traced to obvious differences in these structural properties.
We have deposited p+ a-Si,C:H films by reactive magnetron sputtering from boron doped target with 1 at.% B. We have investigated the influence of H2 pressure on the electrical and microstructural properties of the doped a-Si,C:H films. The boron concentration in the film is ∼2–4×1020cm−3. The incorporation of B atoms decreases by a factor of 2 at the highest H2 pressure. We have obtained films of Taue bandgap ∼1.8–1.84eV with dark conductivity 2–8×10− 6Ω−1cm−1, thermal activation energy ∼0.28–0.33eV and νμτe ∼1–3×10−8cm2/V. This result is comparable with glow discharge B doped a-Si,C:H film. We discuss the film Microstructure, as reflected in infra-red & thermal H evolution spectra, vs. the absolute composition of sputtered boron doped a-Si,C:H films.
A two-step light soaking experiment at high and low intensities provided convincing evidence that defect generation and annealing in a-Si:H are controlled by defect states of different characteristics. We point out that the total defect density by itself cannot uniquely determine the state of material or be described by a single rate equation, even though it might be the only quantity that is experimentally measurable. A system of rate equations for all defect components, therefore, must be established in order to accurately describe the defect kinetics. A simple two-component model in which defects are categorized as “fast” or “slow” is shown to be adequate to explain a variety of experimental results in a consistent fashion.
We report the electronic properties, stability and microstructure of a-Si:H films grown at very high substrate temperature (Ts = 320∼425°C) by DC reactive magnetron sputtering (RMS). The partial pressures of Ar and H2 are fixed at 1.5 and 0.8 mT, respectively, during the deposition. The initial defect state density, determined by the constant photocurrent method (CPM), varies from 2∼5×l015 cm−3with H content changing from 15–10 at.% as Ts increases from 320–375°C. For 100 hrs white light exposure at lW/cm2, a heavily degraded state was obtained with mid–gap state density in the range 2-3×l016cm−3 over this Ts range. These are among the lowest values reported for intrinsic a–Si:H.
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