3,938 research outputs found
Association between Dietary Intake and Faecal Microbiota in Children with Cystic Fibrosis
[EN] A "high-fat, high-energy diet" is commonly recommended for children with cystic fibrosis (CF), leading to negative consequences on dietary patterns that could contribute to altered colonic microbiota. The aim of this study was to assess dietary intake and to identify possible associations with the composition of faecal microbiota in a cohort of children with CF. A cross-sectional observational study was conducted, including a 3-day food record simultaneously with the collection of faecal samples. The results showed a high fat intake (43.9% of total energy intake) and a mean dietary fibre intake of 10.6 g/day. The faecal microbiota was characterised at the phylum level as 54.5% Firmicutes and revealed an altered proportion between Proteobacteria (32%) and Bacteroidota (2.2%). Significant associations were found, including a negative association between protein, meat, and fish intake and Bifidobacterium, a positive association between lipids and Escherichia/Shigella and Streptococcus, a negative association between carbohydrates and Veillonella and Klebsiella, and a positive association between total dietary fibre and Bacteroides and Roseburia. The results reveal that a "high-fat, high-energy" diet does not satisfy dietary fibre intake from healthy food sources in children with CF. Further interventional studies are encouraged to explore the potential of shifting to a high-fibre or standard healthy diet to improve colonic microbiota.The authors would like to thank the Universitat Politècnica de València for the pre-doctoral
contract from Vicerrectorado de Investigación given to JazmÃn Viteri EcheverrÃa (PAID-01-22). This
project was funded with the First Project Grant (PAID-06-22) and Postdoctoral Research Fostering Grant (PAIDPD-22) from Vicerrectorado de Investigación (Universitat Politècnica de València)
awarded to Andrea Asensio-Grau.Viteri-EcheverrÃa, JD.; Calvo-Lerma, J.; Ferriz-Jordán, M.; Garriga, M.; GarcÃa Hernández, J.; Heredia Gutiérrez, AB.; Ribes-Koninckx, C.... (2023). Association between Dietary Intake and Faecal Microbiota in Children with Cystic Fibrosis. Nutrients. 15(24). https://doi.org/10.3390/nu15245013152
The origin of RXJ1856.5-3754 and RXJ0720.4-3125 -- updated using new parallax measurements
RXJ1856 and RXJ0720 are the only young isolated radio-quiet neutron stars
(NSs) for which trigonometric parallaxes were measured. Due to detection of
their thermal emission in X-rays they are important to study NS cooling and to
probe theoretical cooling models. Hence, a precise determination of their age
is essential. Recently, new parallax measurements of RXJ1856 and RXJ0720 were
obtained. Considering that NSs may originate from binary systems that got
disrupted due to an asymmetric supernova, we attempt to identify runaway stars
which may have been former companions to the NS progenitors. Such an
identification would strongly support a particular birth scenario with time and
place. We trace back each NS, runaway star and the centres of possible birth
associations to find close encounters. The kinematic age is then given by the
time since the encounter. We use Monte Carlo simulations to account for
observational uncertainties. Using the most recent parallax measurement of
8.16+/-0.80 mas for RXJ1856, we find that it originated in the U Sco
association 0.46+/-0.05 Myr ago. This is slightly larger than the value we
reported earlier (0.3 Myr). Our result is strongly supported by its current
radial velocity that we predict to be 6+19-20 km/s. This implies an inclination
angle of 88+/-6 deg consistent with the bow shock. No suitable runaway star was
found to be a potential former companion of RXJ1856. Making use of a recent
parallax measurement for RXJ0720 of 3.6+/-1.6 mas, we find that this NS was
possibly born in Tr 10 0.85+/-0.15 Myr ago. This is somewhat larger than the
one obtained using the old parallax value (0.5 Myr). We suggest the B0 runaway
supergiant HIP 43158 as a candidate for a former companion. Then, the current
distance of RXJ0720 to the Sun should be 286+27-23 pc, in agreement with recent
measurements. We then expect the radial velocity of RXJ0720 to be -76+34-17
km/s.Comment: accepted for publication in MNRAS additional supporting material can
be found at http://www.astro.uni-jena.de/~nina/supporting_info.pdf the
abstract has been adjusted to fit the length requirement (RXJ1856 =
RXJ1856.5-3754, RXJ0720 = RXJ0720.4-3125, U Sco = Upper Scorpius, Tr 10 =
Trumpler 10
Electronic structure theory of the hidden order material URuSi
We report a comprehensive electronic structure investigation of the
paramagnetic (PM), the large moment antiferromagnetic (LMAF), and the hidden
order (HO) phases of URuSi. We have performed relativistic
full-potential calculations on the basis of the density functional theory
(DFT), employing different exchange-correlation functionals to treat electron
correlations within the open -shell of uranium. Specifically, we
investigate---through a comparison between calculated and low-temperature
experimental properties---whether the electrons are localized or
delocalized in URuSi. We also performed dynamical mean field theory
calculations (LDA+DMFT) to investigate the temperature evolution of the
quasi-particle states at 100~K and above, unveiling a progressive opening of a
quasi-particle gap at the chemical potential when temperature is reduced. A
detailed comparison of calculated properties with known experimental data
demonstrates that the LSDA and GGA approaches, in which the uranium
electrons are treated as itinerant, provide an excellent explanation of the
available low-temperature experimental data of the PM and LMAF phases. We show
furthermore that due to a materials-specific Fermi surface instability a large,
but partial, Fermi surface gapping of up to 750 K occurs upon antiferromagnetic
symmetry breaking. The occurrence of the HO phase is explained through
dynamical symmetry breaking induced by a mode of long-lived antiferromagnetic
spin-fluctuations. This dynamical symmetry breaking model explains why the
Fermi surface gapping in the HO phase is similar but smaller than that in the
LMAF phase and it also explains why the HO and LMAF phases have the same Fermi
surfaces yet different order parameters. Suitable derived order parameters for
the HO are proposed to be the Fermi surface gap or the dynamic spin-spin
correlation function.Comment: 23 pages, 20 figure
Interatomic potentials for atomistic simulations of the Ti-Al system
Semi-empirical interatomic potentials have been developed for Al, alpha-Ti,
and gamma-TiAl within the embedded atomic method (EAM) by fitting to a large
database of experimental as well as ab-initio data. The ab-initio calculations
were performed by the linear augmented plane wave (LAPW) method within the
density functional theory to obtain the equations of state for a number of
crystal structures of the Ti-Al system. Some of the calculated LAPW energies
were used for fitting the potentials while others for examining their quality.
The potentials correctly predict the equilibrium crystal structures of the
phases and accurately reproduce their basic lattice properties. The potentials
are applied to calculate the energies of point defects, surfaces, planar faults
in the equilibrium structures. Unlike earlier EAM potentials for the Ti-Al
system, the proposed potentials provide reasonable description of the lattice
thermal expansion, demonstrating their usefulness in the molecular dynamics or
Monte Carlo studies at high temperatures. The energy along the tetragonal
deformation path (Bain transformation) in gamma-TiAl calculated with the EAM
potential is in a fairly good agreement with LAPW calculations. Equilibrium
point defect concentrations in gamma-TiAl are studied using the EAM potential.
It is found that antisite defects strongly dominate over vacancies at all
compositions around stoichiometry, indicating that gamm-TiAl is an antisite
disorder compound in agreement with experimental data.Comment: 46 pages, 6 figures (Physical Review B, in press
A theory of intense-field dynamic alignment and high harmonic generation from coherently rotating molecules and interpretation of intense-field ultrafast pump-probe experiments
A theory of ultra-fast pump-probe experiments proposed by us earlier [F.H.M.
Faisal et al., Phys. Rev. Lett. 98, 143001 (2007) and F.H.M. Faisal and A.
Abdurrouf, Phys. Rev. Lett. 100, 123005 (2008)] is developed here fully and
applied to investigate the phenomena of dynamic alignment and high harmonic
generation (HHG) from coherently rotating linear molecules. The theory provides
essentially analytical results for the signals that allow us to investigate the
simultaneous dependence of the HHG signals on the two externally available
control parameters, namely, the relative angle between the polarizations, and
the delay-time between the two pulses. It is applied to investigate the
characteristics of high harmonic emission from nitrogen and oxygen molecules
that have been observed experimentally in a number of laboratories. The results
obtained both in the time-domain and in the frequency-domain are compared with
the observed characteristics as well as directly with the data and are found to
agree remarkably well. In addition we have predicted the existence of a "magic"
polarization angle at which all modulations of the harmonic emission from
nitrogen molecule changes to a steady emission at the harmonic frequency. Among
other things we have also shown a correlation between the existence of the
"magic" or critical polarization angles and the symmetry of the active
molecular orbitals, that is deemed to be useful in connection with the "inverse
problem" of molecular imaging from the HHG data.Comment: 31 pages, 22 figures, and 140 equation
Ising superconductivity and magnetism in NbSe
Recent studies on superconductivity in NbSe have demonstrated a large
anisotropy in the superconducting critical field when the material is reduced
to a single monolayer. Motivated by this recent discovery, we use density
functional theory (DFT) calculations to quantitatively address the
superconducting properties of bulk and monolayer NbSe. We demonstrate that
NbSe is close to a ferromagnetic instability, and analyze our results in
the context of experimental measurements of the spin susceptibility in
NbSe. We show how this magnetic instability, which is pronounced in a
single monolayer, can enable sizeable singlet-triplet mixing of the
superconducting order parameter, contrary to contemporary considerations of the
pairing symmetry in monolayer NbSe, and discuss approaches as to how this
degree of mixing can be addressed quantitatively within our DFT framework. Our
calculations also enable a quantitative description of the large anisotropy of
the superconducting critical field, using DFT calculations of monolayer
NbSe in the normal stateComment: 13 pages, 6 figure
Spartan Daily, May 29, 1952
Volume 40, Issue 154https://scholarworks.sjsu.edu/spartandaily/11742/thumbnail.jp
Individuals and Multilevel Management: A Study of the Perceived Adaptive Capacity of the Goose Management System among Farmers in Sweden
Agricultural damage by geese is a growing problem in Europe and farmers play a key role in the emerging multilevel adaptive management system. This study explored how characteristics associated with the farmer and the farm, along with experience of damage, cognitive appraisals, emotions, and management beliefs were associated with the perceived adaptive capacity of the goose management system among farmers in the south of Sweden (n = 1,067). Survey results revealed that owning a larger farm, a farm closer to water or formally protected areas, along with cultivating cereal and root crops, were associated with geese evoking stronger negative emotions. Further, more previous experience of damage was related to stronger negative emotions and lower levels of perceived adaptive capacity. However, even more important determinants of perceived adaptive capacity were cognitive appraisals, emotions, and management beliefs. Bridging the ties between individual farmers and the system is important for improved multilevel management
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