2,427 research outputs found
The different molecular structure and glycerol-to-fatty acid ratio of palm oils affect their nutritive value in broiler chicken diets
The aim of this study is to assess how the fat molecular structure and its glycerol-to-fatty acid ratio (G : FA) affect the fatty acid (FA) apparent absorption of palm oils in broiler chickens. The experimental diets were the result of a basal diet supplemented with 6% of different palm oils. Native palm oil (N), rich in triacylglycerols, was the positive control (T1), and acid palm oil (A), rich in free FA, was the negative control (T2). In order to improve the nutritive value of A, two different nutritional strategies were performed. The first strategy was achieved by adding increasing amounts of free glycerol (G) (4% (T3), 8% (T4) and 16% (T5)) to A, and the second one by adding increasing amounts of mono- (MAG) and diacylglycerols (DAG), coming from re-esterified palm oil (E) (40% (T6), 70% (T7), and 100% (T8)) to A. As a result, eight dietary treatments were formulated with a G : FA ratio ranging from 0.04 to 0.67. These treatments were randomly assigned to 192 one-day-old female broiler chickens (Ross 308), distributed in 48 cages. The results showed how, by keeping the G : FA ratio constant (0.33 mol/mol), the diet with a high MAG and DAG content (T7) achieved higher saturated FA apparent absorption values than did the diet with a high triacylglycerol content (T1) and this, in turn, more than did the diet with a high free FA content (T4). The behavior of oils with high or low G : FA ratio was dependent on whether G was in a free state or esterified as part of acylglycerol molecules. Thus, increasing amounts of G to A did not enhance the total FA apparent absorption, but rather quite the opposite, even impairing the absorption of mono- and polyunsaturated FA. However, increasing amounts of E (rich in MAG and DAG) to A (rich in FFA) did enhance total FA apparent absorption, primarily due to the increased absorption of saturated FA. In conclusion, the greater the G : FA ratio of a palm oil, the greater the absorption of total FA, as long as G is esterified as part of acylglycerol molecules. Thus, the re-esterification process for obtaining E makes sense in order to give added value to A, achieving even greater digestibility values than does its corresponding N
Purely antiferromagnetic frustrated Heisenberg model in spin ladder compound BaFeSe
The spin dynamics in the block magnetic phase of the iron-based ladder
compound \bfs\ has been studied by means of single crystal inelastic neutron
scattering. Using linear spin wave theory and Monte-Carlo simulations, our
analysis points to a magnetic Heisenberg model with effective frustrated
antiferromagnetic couplings only, able to describe both the exotic block order
and its dynamics. This new and purely antiferromagnetic picture offers a
fruitful perspective to describe multiferroic properties but also understand
the origin of the stripe-like magnetic instability observed under pressure as
well as in other parent compounds with similar crystalline structure
Home Delinquency Rates Are Lower Among ACA Marketplace Households: Evidence From a Natural Experiment
This brief uses administrative income tax data coupled with survey responses from roughly 5,000 households living near the poverty line to estimate how access to the Affordable Care Act’s health insurance Marketplaces have affected households’ experiences of extreme illiquidity, which is measured by delinquencies on home payments. To estimate this relationship, we exploit a natural experiment underway in states that did not expand Medicaid and created by the eligibility rules for Marketplace subsidies. Results suggest that insured households living near the poverty line are better able to make timely rent and mortgage payments compared with similar, uninsured households. Given housing instability’s well-documented links with downstream financial and developmental outcomes, findings presented in this brief suggest that the Affordable Care Act’s health insurance programs have improved the short-term financial well-being of low- and moderate-income households in a way that may have longer term implications
Neutron star in presence of torsion-dilaton field
We develop the general theory of stars in Saa's model of gravity with
propagating torsion and study the basic stationary state of neutron star. Our
numerical results show that the torsion force decreases the role of the gravity
in the star configuration leading to significant changes in the neutron star
masses depending on the equation of state of star matter. The inconsistency of
the Saa's model with Roll-Krotkov-Dicke and Braginsky-Panov experiments is
discussed.Comment: 29 pages, latex, 24 figures, final version. Added: 1)comments on
different possible mass definitions; 2)new sections: a)the inconsistency of
the Saa's model with Roll-Krotkov-Dicke and Braginsky-Panov experiments;
b)stability analysis via catastrophe theory; 3)new figers added and some
figures replaced. 4)new reference
Creating a three dimensional intrinsic electric dipole on rotated CrI bilayers
Two-dimensional (2D) materials are being explored as a novel multiferroic
platform. One of the most studied magnetoelectric multiferroic 2D materials are
antiferromagnetically-coupled (AFM) CrI bilayers. Neglecting magnetism,
those bilayers possess a crystalline point of inversion, which is only removed
by the antiparallel spin configuration among its two constituent monolayers.
The resultant intrinsic electric dipole on those bilayers has a magnitude no
larger than 0.04 pC/m, it points out-of-plane, and it reverts direction when
the--Ising-like--cromium spins are flipped (toward opposite layers {\em versus}
away from opposite layers). The combined presence of antiferromagnetism and a
weak intrinsic electric dipole makes this material a two-dimensional
magnetoelectric multiferroic. Here, we remove the crystalline center of
inversion of the bilayer by a relative rotation of its constituent
monolayers. This process {\em enhances} the out-of-plane intrinsic electric
dipole tenfold with respect to its magnitude in the non-rotated AFM bilayer and
also creates an even stronger and switchable in-plane intrinsic electric
dipole. The ability to create a three-dimensional electric dipole is important,
because it enhances the magnetoelectric coupling on this experimentally
accessible 2D material, which is explicitly calculated here as well.Comment: Accepted at PRB on May 1, 202
Quantum fluctuations for drag free geodesic motion
The drag free technique is used to force a proof mass to follow a geodesic
motion. The mass is protected from perturbations by a cage, and the motion of
the latter is actively controlled to follow the motion of the proof mass. We
present a theoretical analysis of the effects of quantum fluctuations for this
technique. We show that a perfect drag free operation is in principle possible
at the quantum level, in spite of the back action exerted on the mass by the
position sensor.Comment: 4 pages, 1 figure, RevTeX, minor change
Recommended from our members
Beagle 2: Mission to Mars — current status
Beagle 2, developed in the UK, was launched on June 2, 2003. It landed on Mars on December 25th, 2003 in Isidis Planitia, a large sedimentary basin. To date, the team is awaiting signals from the Beagle 2 lander. Current status of the mission will be reported
The Equivalence Principle in the Non-baryonic Regime
We consider the empirical validity of the equivalence principle for
non-baryonic matter. Working in the context of the TH\epsilon\mu formalism, we
evaluate the constraints experiments place on parameters associated with
violation of the equivalence principle (EVPs) over as wide a sector of the
standard model as possible. Specific examples include new parameter constraints
which arise from torsion balance experiments, gravitational red shift,
variation of the fine structure constant, time-dilation measurements, and
matter/antimatter experiments. We find several new bounds on EVPs in the
leptonic and kaon sectors.Comment: 22 pages, late
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