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Medium-chain triglycerides and conjugated linoleic acids in beverage form increase satiety and reduce food intake in humans
Both developed and developing countries are seeing increasing trends of obesity in people young and old. It is thought that satiety may play a role in the prevention of obesity by increasing satiety and reducing energy intake. We hypothesized that medium-chain triglycerides (MCT) would increase satiety and decrease food intake compared with conjugated linoleic acid (CLA) and a control oil. Nineteen healthy participants were tested on 3 separate occasions, where they consumed a beverage test breakfast containing (1) vegetable oil (control), (2) CLA, or (3) MCT. Participants self-requested an ad libitum sandwich buffet lunch. Time between meals, satiety from visual analog scales, energy intake at lunch, and intake for the rest of the day using weighed food diaries were measured. The results indicated that the time until a meal request was significantly different between the 3 meals (P=.016); however, there were no differences in intakes at the ad libitum lunch (P>.05). The CLA breakfast generated the greatest delay in meal time request. There was a difference between the control lipid compared with both the CLA and MCT for energy intake over the remainder of the test day and for total energy intake on the test day (P.05). Both CLA and MCT increased satiety and reduced energy intake, indicating a potential role in aiding the maintenance of energy balance
Centrifugal acceleration in the magnetotail lobes
Combined Cluster EFW and EDI measurements have shown that cold ion outflow in the magnetospheric lobes dominates the hydrogen ion outflow from the Earth's atmosphere. The ions have too low kinetic energy to be measurable with particle instruments, at least for the typical spacecraft potential of a sunlit spacecraft in the tenuous lobe plasmas outside a few <I>R</I><sub>E</sub>. The measurement technique yields both density and bulk velocity, which can be combined with magnetic field measurements to estimate the centrifugal acceleration experienced by these particles. We present a quantitative estimate of the centrifugal acceleration, and the velocity change with distance which we would expect due to centrifugal acceleration. It is found that the centrifugal acceleration is on average outward with an average value of about of 5 m s<sup>&minus;2</sup>. This is small, but acting during long transport times and over long distances the cumulative effect is significant, while still consistent with the relatively low velocities estimated using the combination of EFW and EDI data. The centrifugal acceleration should accelerate any oxygen ions in the lobes to energies observable by particle spectrometers. The data set also put constraints on the effectiveness of any other acceleration mechanisms acting in the lobes, where the total velocity increase between 5 and 19 <I>R</I><sub>E</sub> geocentric distance is less than 5 km s<sup>&minus;1</sup>
MCG+00-32-16: An Irregular Galaxy Close to the Lowest Redshift Absorber on the 3C 273 Line of Sight
MCG+00-32-16 is the galaxy closest in position-velocity space to the lowest
redshift Ly absorber along the line-of-sight to the quasar 3C 273. Its
projected separation is 204 (d/19 Mpc) kpc, where d is the distance from the
Milky Way to the galaxy, and the redshift difference is only 94 km/s; HI
1225+01 is slightly closer in projected separation to the absorber, but has a
greater redshift difference. We present HI synthesis array mapping and CCD
photometry in B and R for MCG+00-32-16. The HI disk is rotating in such a way
that the side of the galaxy closer to the sight-line to the quasar has the
larger velocity difference from the absorber. The absorber may be a ``failed
dwarf'' member of a poor galaxy group of which MCG+00-32-16 and HI 1225+01 are
the only members to have formed stars.Comment: 14 pages, 9 figures, accepted by Astrophysical Journa
Lava channel formation during the 2001 eruption on Mount Etna: evidence for mechanical erosion
We report the direct observation of a peculiar lava channel that was formed
near the base of a parasitic cone during the 2001 eruption on Mount Etna.
Erosive processes by flowing lava are commonly attributed to thermal erosion.
However, field evidence strongly suggests that models of thermal erosion cannot
explain the formation of this channel. Here, we put forward the idea that the
essential erosion mechanism was abrasive wear. By applying a simple model from
tribology we demonstrate that the available data agree favorably with our
hypothesis. Consequently, we propose that erosional processes resembling the
wear phenomena in glacial erosion are possible in a volcanic environment.Comment: accepted for publication in Physical Review Letter
Performance of an Operating High Energy Physics Data Grid: D0SAR-Grid
The D0 experiment at Fermilab's Tevatron will record several petabytes of
data over the next five years in pursuing the goals of understanding nature and
searching for the origin of mass. Computing resources required to analyze these
data far exceed capabilities of any one institution. Moreover, the widely
scattered geographical distribution of D0 collaborators poses further serious
difficulties for optimal use of human and computing resources. These
difficulties will exacerbate in future high energy physics experiments, like
the LHC. The computing grid has long been recognized as a solution to these
problems. This technology is being made a more immediate reality to end users
in D0 by developing a grid in the D0 Southern Analysis Region (D0SAR),
D0SAR-Grid, using all available resources within it and a home-grown local task
manager, McFarm. We will present the architecture in which the D0SAR-Grid is
implemented, the use of technology and the functionality of the grid, and the
experience from operating the grid in simulation, reprocessing and data
analyses for a currently running HEP experiment.Comment: 3 pages, no figures, conference proceedings of DPF04 tal
Underwater blast loading of partially submerged sandwich composite materials in relation to air blast loading response
The research presented in this paper focusses on the underwater blast resilience of a hybrid composite sandwich panel, consisting of both glass-fibre and carbon-fibre. The hybrid fibres were selected to optimise strength and stiffness during blast loading by promoting fibre interactions. In the blast experiment, the aim was to capture full-field panel deflection during large-scale underwater blast using high-speed 3D Digital Image Correlation (DIC). The composite sandwich panel was partially submerged and subjected to a 1 kg PE7 charge at 1 m stand-off. The charge was aligned with the centre of the panel at a depth of 275 mm and mimicked the effect of a near-field subsurface mine. The DIC deflection data shows that the horizontal cross-section of the panel deforms in a parabolic shape until excessive deflection causes core shear cracking. The panel then forms the commonly observed “bathtub” deformation shape. DIC data highlighted the expected differences in initial conditions compared to air-blast experiments, including the pre-strains caused by the mass of water (hydrostatic pressure). Furthermore, water depth was shown to significantly influence panel deflection, strain and hence damage sustained under these conditions. Panel deformations and damage after blast was progressively more severe in regions deeper underwater, as pressures were higher and decayed slower compared to regions near the free surface.An identical hybrid composite sandwich panel was subjected to air blast; one panel underwent two 8 kg PE7 charges in succession at 8 m stand-off. DIC was also implemented to record the panel deformations during air blast. The air and underwater blast tests represent two different regimes of blast loading: one far-field in air and one near-field underwater. The difference in deflection development, caused by the differing fluid mediums and stand-off distances, is apparent from the full-field results. During underwater blast the panel underwent peak pressure loading of approximately 52.6 MPa whilst during air blast the panel was subjected to 67.7 kPa followed by 68.9 kPa peak pressure loads in succession. The two experiments demonstrate the response of the same hybrid composite sandwich panel under two differing blast regimes.The post-blast damage and strength of the hybrid panels following air and underwater blasts were evaluated. Post-blast testing revealed that the underwater blast causes significantly more damage compared to air blast, particularly debonding between the skins and core. The air blast panel sustains no visible rear skin/core debonding, whereas 13 regions of rear-face debonds are identified on the underwater blast panel. Sustaining no front-skin breakage was advantageous for retaining a high proportion of the compressive modulus for this hybrid layup following underwater blast. Damage mechanisms were interrelated. Determining the most detrimental type is not straightforward in real explosive and non-idealised experiments, however debonding was understandably shown to be significant. A further study to isolate failure modes and improve in situ instrumentation is ongoing
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