3,087 research outputs found
Grain Characteristics, Chemical Composition, and Functional Properties of Rye (Secale cereale L.) As Influenced by Genotype and Harvest Year
Grain characteristic, chemical composition, and functional properties of rye were measured in 19 different cultivars grown in one location in up to 3 years. The cultivars included 8 adapted hybrids, 7 adapted population cultivars, and 4 nonadapted population cultivars. The results showed a significant influence of both harvest year and genotype on grain characteristics, chemical composition, and functional properties of the grain. Multivariate data analysis confirmed that the variations in the data were explained by yearly and genotype differences. Calculations of variance components showed that the variations in plant height, harvest yield, and protein content were mainly due to genotype differences and to a lesser extent to differences among harvest years. The kernel weight, hardness index, and content of dietary fiber components, however, were more strongly influenced by the harvest year than by the genotype. Differences in starch properties measured by falling number (FN), amylograph peak viscosity, and temperature at peak viscosity were more strongly influenced by harvest year. The water absorption was strongly influenced by genotype effects, compared to yearly differences. FN and amylograph peak temperature were positively correlated (r = 0.94). No correlation was found between the water absorption and the relative proportion of water-extractable arabinoxylan (AX) compared to the total AX content. However, the degree of ferulic acid cross-linking showed a negative correlation (r = -0.70) with the water absorption
Cultivar and Year-to-Year Variation of Phytosterol Content in Rye (Secale cereale L.)
Intake of phytosterols (and -stanols) has been shown to decrease the level of low-density lipoprotein cholesterol and thus protect against development of cardiovascular diseases. Therefore, studies on the cultivar and year-to-year variation in phytosterol content in rye grains have been performed. The phytosterol content and composition of different rye cultivars, grown under identical conditions on the same field in three consecutive years, were analyzed. Both cultivar and year-to-year variation in sterol content were statistically significant (p < 0.0001). The total sterol content varied from 1007 ± 21 mg/kg in the highest yielding cultivar, Tsulpan 3, to 761 ± 10 mg/kg in the lowest yielding cultivar (Amando in the 1999 harvest). Because the meteorological conditions varied substantially between the different years, it was possible to deduce the impact of varying weather conditions on phytosterol content in the different cultivars. The studied cultivars had all the lowest phytosterol contents in the dry and warm harvest season of 1999. Although there were statistically significant cultivar and year-to-year variations in the sterol composition (p < 0.0001), these were only between 2 and 4% of the total sterol content
Fast, exact CMB power spectrum estimation for a certain class of observational strategies
We describe a class of observational strategies for probing the anisotropies
in the cosmic microwave background (CMB) where the instrument scans on rings
which can be combined into an n-torus, the {\em ring torus}. This class has the
remarkable property that it allows exact maximum likelihood power spectrum
estimation in of order operations (if the size of the data set is )
under circumstances which would previously have made this analysis intractable:
correlated receiver noise, arbitrary asymmetric beam shapes and far side lobes,
non-uniform distribution of integration time on the sky and partial sky
coverage. This ease of computation gives us an important theoretical tool for
understanding the impact of instrumental effects on CMB observables and hence
for the design and analysis of the CMB observations of the future. There are
members of this class which closely approximate the MAP and Planck satellite
missions. We present a numerical example where we apply our ring torus methods
to a simulated data set from a CMB mission covering a 20 degree patch on the
sky to compute the maximum likelihood estimate of the power spectrum
with unprecedented efficiency.Comment: RevTeX, 14 pages, 5 figures. A full resolution version of Figure 1
and additional materials are at http://feynman.princeton.edu/~bwandelt/RT
Higgsino Dark Matter in a SUGRA Model with Nonuniversal Gaugino Masses
We study a specific SUGRA model with nonuniversal gaugino masses as an
alternative to the minimal SUGRA model in the context of supersymmetric dark
matter. The lightest supersymmetric particle in this model comes out to be a
Higgsino dominated instead of a bino dominated lightest neutralino. The thermal
relic density of this Higgsino dark matter is somewhat lower than the
cosmologically favoured range, which means it may be only a subdominant
component of the cold dark matter. Nonetheless, it predicts favourable rates of
indirect detection, which can be seen in square-km size neutrino telescopes.Comment: Version to appear in Phys. Rev. D. A few references added in the
bibliography and a comment added in Section 2. LaTex, 16 pages, 4 figure
Scalar Dark Matter From Theory Space
The scalar dark matter candidate in a prototypical theory space little Higgs
model is investigated. We review all details of the model pertinent to dark
matter. We perform a thermal relic density calculation including couplings to
the gauge and Higgs sectors of the model. We find two regions of parameter
space that give acceptable dark matter abundances. The first region has a dark
matter candidate with a mass of order 100 GeV, the second region has a heavy
candidate with a mass greater than about 500 GeV$. The dark matter candidate in
either region is an admixture of an SU(2) triplet and an SU(2) singlet, thereby
constituting a WIMP (weakly interacting massive particle).Comment: 18 pages, 2 figures, version to appear in PR
Risk analysis of a distillation unit
A risk analysis of a batch distillation unit is de-scribed. The analysis has been carried out at several stages during plant design, construction, and operation. The costs, quality, and benefits is using the methods are described
The extended empirical process test for non-Gaussianity in the CMB, with an application to non-Gaussian inflationary models
In (Hansen et al. 2002) we presented a new approach for measuring
non-Gaussianity of the Cosmic Microwave Background (CMB) anisotropy pattern,
based on the multivariate empirical distribution function of the spherical
harmonics a_lm of a CMB map. The present paper builds upon the same ideas and
proposes several improvements and extensions. More precisely, we exploit the
additional information on the random phases of the a_lm to provide further
tests based on the empirical distribution function. Also we take advantage of
the effect of rotations in improving the power of our procedures. The suggested
tests are implemented on physically motivated models of non-Gaussian fields;
Monte-Carlo simulations suggest that this approach may be very promising in the
analysis of non-Gaussianity generated by non-standard models of inflation. We
address also some experimentally meaningful situations, such as the presence of
instrumental noise and a galactic cut in the map.Comment: 15 pages, 6 figures, submitted to Phys. Rev.
Protein sequence and structure: Is one more fundamental than the other?
We argue that protein native state structures reside in a novel "phase" of
matter which confers on proteins their many amazing characteristics. This phase
arises from the common features of all globular proteins and is characterized
by a sequence-independent free energy landscape with relatively few low energy
minima with funnel-like character. The choice of a sequence that fits well into
one of these predetermined structures facilitates rapid and cooperative
folding. Our model calculations show that this novel phase facilitates the
formation of an efficient route for sequence design starting from random
peptides.Comment: 7 pages, 4 figures, to appear in J. Stat. Phy
Direct detection of neutralino dark matter in supergravity
The direct detection of neutralino dark matter is analysed in general
supergravity scenarios, where non-universal soft scalar and gaugino masses can
be present. In particular, the theoretical predictions for the
neutralino-nucleon cross section are studied and compared with the sensitivity
of dark matter detectors. We take into account the most recent astrophysical
and experimental constraints on the parameter space, including the current
limit on B(Bs-> mu+ mu-). The latter puts severe limitations on the dark matter
scattering cross section, ruling out most of the regions that would be within
the reach of present experiments. We show how this constraint can be softened
with the help of appropriate choices of non-universal parameters which increase
the Higgsino composition of the lightest neutralino and minimise the chargino
contribution to the b->s transition.Comment: 27 pages, 22 figure
Searching for hidden mirror symmetries in CMB fluctuations from WMAP 7 year maps
We search for hidden mirror symmetries at large angular scales in the WMAP 7
year Internal Linear Combination map of CMB temperature anisotropies using
global pixel based estimators introduced for this aim. Two different axes are
found for which the CMB intensity pattern is anomalously symmetric (or
anti-symmetric) under reflection with respect to orthogonal planes at the
99.84(99.96)% CL (confidence level), if compared to a result for an arbitrary
axis in simulations without the symmetry. We have verified that our results are
robust to the introduction of the galactic mask. The direction of such axes is
close to the CMB kinematic dipole and nearly orthogonal to the ecliptic plane,
respectively. If instead the real data are compared to those in simulations
taken with respect to planes for which the maximal mirror symmetry is generated
by chance, the confidence level decreases to 92.39 (76.65)%. But when the
effect in question translates into the anomalous alignment between normals to
planes of maximal mirror (anti)-symmetry and these natural axes mentioned. We
also introduce the representation of the above estimators in the harmonic
domain, confirming the results obtained in the pixel one. The symmetry anomaly
is shown to be almost entirely due to low multipoles, so it may have a
cosmological and even primordial origin. Contrary, the anti-symmetry one is
mainly due to intermediate multipoles that probably suggests its
non-fundamental nature. We have demonstrated that these anomalies are not
connected to the known issue of the low variance in WMAP observations and we
have checked that axially symmetric parts of these anomalies are small, so that
the axes are not the symmetry ones.Comment: 18 pages, 10 figures, 2 tables. Consideration and discussion
expanded, 5 figures and 1 table added, main conclusions unchange
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