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Recently, large-scale trials of behavioural interventions have failed to show improvements in pregnancy outcomes. They have, however, shown that lifestyle support improves maternal diet and physical activity during pregnancy, and can reduce weight gain. This suggests that pregnancy, and possibly the whole periconceptional period, represents a ‘teachable moment’ for changes in diet and lifestyle, an idea that was made much of in the recent report of the Chief Medical Officer for England. The greatest challenge with all trials of diet and lifestyle interventions is to engage people and to sustain this engagement. With this in mind, we propose a design of intervention that aims simultaneously to engage women through motivational conversations and to offer access to a digital platform that provides structured support for diet and lifestyle change. This intervention design therefore makes best use of learning from the trials described above and from recent advances in digital intervention design.
NASA's NuSTAR observatory is the first focusing hard X-ray telescope. Launched in June 2012, NuSTAR is sensitive in the 3–79 keV range with unprecedented ~17″ FWHM angular resolution above 12 keV, a result of its multilayer-coated optics and 10-m focal length. With its large effective area (900 cm2 at 10 keV), NuSTAR has point-source sensitivity ~100 times better than previous hard X-ray telescopes. Here we describe NuSTAR and its planned work on rotation-powered pulsars and magnetars during its nominal 2-yr baseline mission that has just commenced.
The crystalline quality of bonded Silicon-On-Insulator (SOI) wafers were examined by spectroscopic ellipsometry and Raman spectroscopy. Both techniques detect slight structural defects in the SOI layer. If a pure crystalline silicon dielectric function is assumed for the SOI layer, the spectroscopic ellipsometry data fitting yields an unacceptably large discrepancy between the experimental and modeled data. The best fits for all the samples result in a dielectric function of the SOI layer that consists of a physical mixture of crystalline silicon and about 4 % to 7 % of amorphous silicon. Using such a mixture indicates that there are still some defects in the SOI layer when compared with the high-quality bulk crystalline silicon. This observation is further supported by Raman spectroscopy measurements. The Raman spectra of all SOI samples exhibit a feature at about 495 cm−1 that is not observed in the crystalline silicon spectrum. Features similar to the 495 cm−1 feature have been reported in the literature and attributed to dislocations or faults in the silicon lattice.
A primary proposal of the Cowan target article is that capacity limits arise in working memory because only 4 chunks of information can be attended at one time. This implies a single, unitary attentional focus or resource; we instead propose that relatively independent attentional mech- anisms operate within different cognitive subsystems depending on the demands of the current stimuli and tasks.
Many previous studies have demonstrated that the
visual N1 component is larger for attended-location stimuli
than for unattended-location stimuli. This difference is
observed typically only for tasks involving a discrimination
of the attended-location stimuli, suggesting that the N1
wave reflects a discrimination process that is applied
to the attended location. The present study tested this
hypothesis by examining the N1 component elicited by attended
stimuli under conditions that either required or did not
require the subject to perform a discrimination. Specifically,
the N1 elicited by foveal stimuli during choice-reaction
time (RT) tasks was compared with the N1 elicited by identical
stimuli during simple-RT tasks. In three experiments, a
larger posterior N1 was observed in choice-RT tasks than
in simple-RT tasks, even when several potential confounds
were eliminated (e.g., arousal and motor preparation).
This N1 discrimination effect was observed even when no
motor response was required and was present for both color-
and form-based discriminations. Moreover, this discrimination
effect was equally large for easy and difficult discriminations,
arguing against a simple resource-based explanation of
the present results. Instead, the results of this study
are consistent with the hypothesis that the visual N1 component
reflects the operation of a discrimination process within
the focus of attention.
The gate tunneling current in ultrathin gate dielectric NMOSFETs with positive gate bias is due to the tunneling of electrons from the conduction and valence bands of the substrate. Valence-band electrons tunnel from the substrate of NMOS devices when the valence-band edge in the substrate rises above the conduction-band edge in the substrate. This paper reports experimental trends in the contribution of valence-band electrons tunneling to the gate current of NMOSFETs with gate oxides composed of pure SiO2. The large gate tunneling current can be reduced by replacing the conventional SiO2 gate dielectric with alternative dielectrics with larger dielectric constants. This paper reports the effect of replacing SiO2 with alternative dielectrics on the contribution of valence-band electron tunneling to the gate current. Simulations are carried out for composite SiO2/Ta2O5 gate dielectric structures.
The gastric and tracheal flora of 142 consecutive patients receiving stress ulcer prophylaxis were investigated, identifying identical isolates by typing. Furthermore, the growth pattern of normal respiratory bacteria and organisms causing ventilation pneumonia at different pH values and the in vitro effect of sucralfate and bismuth subsalicylate on these bacteria in simulated gastric fluid were studied. The results obtained were as follows: (1) with rising gastric pH bacterial counts in gastric aspirates, especially gram-negatives, increased significantly; (2) in 45 (31.7%) of the patients identical organisms were first isolated in gastric samples and one to two days later in tracheal secretions; (3) ventilation pneumonia was significantly more frequent in patients with high gastric pH; (4) pathogens causing ventilation pneumonia grew well in simulated gastric fluid at higher pH values, unlike normal respiratory organisms; and (5) sucralfate and bismuth subsalicylate showed antibacterial activity against frequent causative organisms of ventilation pneumonia.
There is a great clinical need for readily available volume replacement fluids with the property of oxygen transport. From the fluorocarbone emulsions only stromafree hemoglobin solutions seem to meet the essential requirements of oxygen transport and delivery at the tissue level. However, the high oxygen affinity and the short intravascular persistence have been preventing, up until now, the application of hemoglobin solutions for blood replacement.
Recently, a modified hemoglobin solution with a decreased oxygen affinity and a long intravascular persistence, has been produced by binding pyridoxalphosphate to the hemoglobin and its subsequent crosslinking. The hemodynamics and oxygen unloading capacity of this pyridoxalated polyhemoglobin have been investigated in a model of total blood exchange.
1. The frequency of association between methanogenic bacteria and ovine rumen ciliates was studied in the rumen fluid of a fistulated sheep.
2. A period of fasting and flushing of the rumen content with nitrogen resulted in a relatively high association, whereas the intake of food and flushing with hydrogen caused a detachment of the methanogenic bacteria from the ciliates.
3. The changes in the frequency of association can be correlated with the relative attribution to the H2 production by hydrogenogenic bacteria and rumen ciliates.
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