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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
Blinded patient preference for morphine compared to placebo in the setting of chronic refractory breathlessness – an exploratory study
Context Patients’ preference for morphine therapy has received little attention in the setting of chronic refractory breathlessness. However, this is one important factor in considering longer term therapy. Objectives The aim of this secondary analysis is to explore blinded patient preference of morphine compared to placebo for this indication and to define any predictors of preference. Methods Data were pooled from three randomized, double-blind, crossover, placebo-controlled studies of morphine (four days each) in chronic refractory breathlessness. Blinded patient preferences were chosen at the end of each study. A multivariable regression model was used to establish patient predictors of preference. Results Sixty-five participants provided sufficient data (60 males; median age 74 years; heart failure 55%, chronic obstructive pulmonary disease 45%; median Eastern Cooperative Oncology Group performance status 2). Forty-three percent of participants preferred morphine (32% placebo and 25% no preference). Morphine preference and younger age were strongly associated: odds ratio = 0.85, 95% confidence interval 0.78, 0.93;
Performance of Sentinel-2 NDVI for assessing the relationship between vegetation and soil moisture under extreme drought conditions
Initial indications are that the enhanced spatial and spectral resolution of Sentinel-2 would allow for better assess- ment of vegetation condition, and consequently improved application in conditions of moisture deficit/drought. Although NDVI and other indices are well established methods in drought monitoring, particularly at larger scales, little research has examined the suitability of Sentinel-2. While the utility of Landsat-8 NDVI in revealing local scale plant-soil dynamics has been explored, challenges around resolution have emerged. The principal aim of this study was to determine the extent to which NDVI time series reflects soil moisture conditions, and whether this offers an improvement over Landsat-8. On the basis of exposure to drought over the study period (Jul 2015-Mar 2017), availability of cloud-free imagery and measured soil moisture, five sites in South-Western United States were selected. These sites, normally dry to arid, were classified as being in various states of drought, but in general this represented extension and recession of a significant drought event. A secondary focus of the paper therefore was the performance of Sentinel-2 NDVI under extreme conditions. As far as we are aware, this represents the first study of this kind using Sentinel-2.
Following supervised classification, NDVI time series for areas of 1km radius around the monitoring sta- tions were calculated. Sentinel-2 NDVI variants were calculated using Bands 8 (10m), 5, 6, 7, and 8A (20m). Landsat-8 NDVI was calculated at 30m resolution. Pearson correlation analysis was undertaken of all NDVI time series against soil moisture at all measured soil depths. In order to assess the difference in correlation strength produced from using the Sentinel-2 red-edge bands, compared to the standard NIR band, a principal component analysis (PCA) was conducted. This was performed on the combination of all Sentinel-2 bands and the combination of the red-edge bands. Performance of the Sentinel-2 red-edge NDVI time series against the standard NIR band was also evaluated using a Steiger comparison test.
While no significant correlations between Landsat-8 NDVI and measured soil moisture were found, high significant correlations were present between moisture at depths of <30cm and Sentinel-2 NDVI at three sites. No significant positive correlations were found at two sites, despite similar conditions to the others. These sites were characterised by much lower vegetation cover, suggesting a minimum cover threshold of ≈30-40% is required. The PCA shows that at all sites of significant positive moisture-NDVI correlations, the linear combination of the red-edge bands produced stronger correlations than the poorer spectral, but higher spatial resolution band. NDVI calculated using the higher spectral resolution bands may therefore be of greater use in this context than the higher spatial resolution option. However, each site/measurement with a relationship present also had an individual component which out-performed the PCA combination, most likely related to the spectral characteristics of local vegetation. These results suggest high potential for the application of Sentinel-2 NDVI in drought monitoring, even in extreme environments, thus allowing us to further our understanding of local scale plant-soil dynamics under such conditions
Air Traffic Simulation Technology for High-Population Metroplexes
IAI's MetroSim optimizes air traffic by simulating departures, arrivals, and activity in air and onthe ground in busy metroplexes, where flights impact each other at a single airport and among traffic at nearby airports. MetroSim evolved out of several NASA SBIR/STTR Awards and has since been used by NASA for flight simulation analysis. MetroSim has also been integrated with FAA and DOT technology, has produced studies for the Port Authority of New York and New Jersey, and is under development to support the Nav
A review of sea-spray aerosol source functions using a large global set of sea salt aerosol concentration measurements
Sea-spray aerosols (SSA) are an important part of the climate system because
of their effects on the global radiative budget – both directly as scatterers and
absorbers of solar and terrestrial radiation, and indirectly as cloud
condensation nuclei (CCN) influencing cloud formation, lifetime, and
precipitation. In terms of their global mass, SSA have the largest
uncertainty of all aerosols. In this study we review 21 SSA source functions
from the literature, several of which are used in current climate models. In
addition, we propose a~new function. Even excluding outliers, the global annual
SSA mass produced spans roughly 3–70 Pg yr<sup>−1</sup> for the different
source functions, for particles with dry diameter <i>D</i><sub>p</sub> < 10 μm,
with relatively little interannual variability for a given
function. The FLEXPART Lagrangian particle dispersion model was run in
backward mode for a large global set of observed SSA concentrations,
comprised of several station networks and ship cruise measurement campaigns.
FLEXPART backward calculations produce gridded emission sensitivity fields,
which can subsequently be multiplied with gridded SSA production fluxes in order to
obtain modeled SSA concentrations. This allowed us to efficiently and simultaneously evaluate all
21 source functions against the measurements. Another
advantage of this method is that source-region information on wind speed and
sea surface temperatures (SSTs) could be stored and used for improving the
SSA source function parameterizations. The best source functions reproduced
as much as 70% of the observed SSA concentration variability at
several stations, which is comparable with "state of the art" aerosol
models. The main driver of SSA production is wind, and we found that the best
fit to the observation data could be obtained when the SSA production is
proportional to <i>U</i><sub>10</sub><sup>3.5</sup>, where
<i>U</i><sub>10</sub> is the source region averaged
10 m wind speed. A strong influence of SST on SSA production, with
higher temperatures leading to higher production, could be detected as well,
although the underlying physical mechanisms of the SST influence remains
unclear. Our new source function with wind speed and temperature dependence
gives a global SSA production for particles smaller than
<i>D</i><sub>p</sub> < 10 μm of 9 Pg yr<sup>−1</sup>, and is the best fit to the observed
concentrations
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
Plasma convection in the magnetotail lobes: statistical results from Cluster EDI measurements
A major part of the plasma in the Earth's magnetotail is populated through transport of plasma from the solar wind via the magnetotail lobes. In this paper, we present a statistical study of plasma convection in the lobes for different directions of the interplanetary magnetic field and for different geomagnetic disturbance levels. The data set used in this study consists of roughly 340 000 one-minute vector measurements of the plasma convection from the Cluster Electron Drift Instrument (EDI) obtained during the period February 2001 to June 2007. The results show that both convection magnitude and direction are largely controlled by the interplanetary magnetic field (IMF). For a southward IMF, there is a strong convection towards the central plasma sheet with convection velocities around 10 km s<sup>&minus;1</sup>. During periods of northward IMF, the lobe convection is almost stagnant. A <I>B<sub>y</sub></I> dominated IMF causes a rotation of the convection patterns in the tail with an oppositely directed dawn-dusk component of the convection for the northern and southern lobe. Our results also show that there is an overall persistent duskward component, which is most likely a result of conductivity gradients in the footpoints of the magnetic field lines in the ionosphere
The Population of Damped Lyman-alpha and Lyman Limit Systems in the Cold Dark Matter Model
Lyman limit and damped Lyman-alpha absorption systems probe the distribution
of collapsed, cold gas at high redshift. Numerical simulations that incorporate
gravity and gas dynamics can predict the abundance of such absorbers in
cosmological models. We develop a semi-analytical method to correct the
numerical predictions for the contribution of unresolved low mass halos, and we
apply this method to the Katz et al. (1996) simulation of the standard cold
dark matter model (, , , ). Using
this simulation and higher resolution simulations of individual low mass
systems, we determine the relation between a halo's circular velocity and
its cross section for producing Lyman limit or damped absorption. We combine
this relation with the Press-Schechter formula for the abundance of halos to
compute the number of absorbers per unit redshift. The resolution correction
increases the predicted abundances by about a factor of two at z=2, 3, and 4,
bringing the predicted number of damped absorbers into quite good agreement
with observations. Roughly half of the systems reside in halos with circular
velocities v_c>100\kms and half in halos with 35\kms. Halos
with v_c>150\kms typically harbor two or more systems capable of producing
damped absorption. Even with the resolution correction, the predicted abundance
of Lyman limit systems is a factor of three below observational estimates,
signifying either a failure of standard CDM or a failure of these simulations
to resolve the systems responsible for most Lyman limit absorption. By
comparing simulations with and without star formation, we find that depletion
of the gas supply by star formation affects absorption line statistics at
only for column densities exceeding .Comment: AASlatex, 17 pages w/ 3 embedded ps figures. Submitted to Ap
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