2,802 research outputs found
Oscillatory relaxation of zonal flows in a multi-species stellarator plasma
The low frequency oscillatory relaxation of zonal potential perturbations is
studied numerically in the TJ-II stellarator (where it was experimentally
detected for the first time). It is studied in full global gyrokinetic
simulations of multi-species plasmas. The oscillation frequency obtained is
compared with predictions based on single-species simulations using simplified
analytical relations. It is shown that the frequency of this oscillation for a
multi-species plasma can be accurately obtained from single-species
calculations using extrapolation formulas. The damping of the oscillation and
the influence of the different inter-species collisions is studied in detail.
It is concluded that taking into account multiple kinetic ions and electrons
with impurity concentrations realistic for TJ-II plasmas allows to account for
the values of frequency and damping rate in zonal flows relaxations observed
experimentally.Comment: 11 figures, 22 page
PDB60 ASSOCIATION OF INADEQUATE METABOLIC CONTROL AND CO-MORBIDITIES AND HEALTH RESOURCE UTILIZATION IN PATIENTS WITH DIABETES MELLITUS IN A SPANISH POPULATION
The value of gut microbiota to predict feed efficiency and growth of rabbits under different feeding regimes
Gut microbiota plays an important role in nutrient absorption and could impact rabbit feed efciency.
This study aims at investigating such impact by evaluating the value added by microbial information
for predicting individual growth and cage phenotypes related to feed efciency. The dataset
comprised individual average daily gain and cage-average daily feed intake from 425 meat rabbits, in
which cecal microbiota was assessed, and their cage mates. Despite microbiota was not measured in
all animals, consideration of pedigree relationships with mixed models allowed the study of cageaverage traits. The inclusion of microbial information into certain mixed models increased their
predictive ability up to 20% and 46% for cage-average feed efciency and individual growth traits,
respectively. These gains were associated with large microbiability estimates and with reductions in
the heritability estimates. However, large microbiabililty estimates were also obtained with certain
models but without any improvement in their predictive ability. A large proportion of OTUs seems to
be responsible for the prediction improvement in growth and feed efciency traits, although specifc
OTUs taxonomically assigned to 5 diferent phyla have a higher weight. Rabbit growth and feed
efciency are infuenced by host cecal microbiota, thus considering microbial information in models
improves the prediction of these complex phenotypes.info:eu-repo/semantics/publishedVersio
Use of Bayes factors to evaluate the effects of host genetics, litter and cage on the rabbit cecal microbiota
Background: The rabbit cecum hosts and interacts with a complex microbial ecosystem that contributes to the variation of traits of economic interest. Although the influence of host genetics on microbial diversity and specific microbial taxa has been studied in several species (e.g., humans, pigs, or cattle), it has not been investigated in rabbits. Using a Bayes factor approach, the aim of this study was to dissect the effects of host genetics, litter and cage on 984 microbial traits that are representative of the rabbit microbiota. Results: Analysis of 16S rDNA sequences of cecal microbiota from 425 rabbits resulted in the relative abundances of 29 genera, 951 operational taxonomic units (OTU), and four microbial alpha-diversity indices. Each of these microbial traits was adjusted with mixed linear and zero-inflated Poisson (ZIP) models, which all included additive genetic, litter and cage effects, and body weight at weaning and batch as systematic factors. The marginal posterior distributions of the model parameters were estimated using MCMC Bayesian procedures. The deviance information criterion (DIC) was used for model comparison regarding the statistical distribution of the data (normal or ZIP), and the Bayes factor was computed as a measure of the strength of evidence in favor of the host genetics, litter, and cage effects on microbial traits. According to DIC, all microbial traits were better adjusted with the linear model except for the OTU present in less than 10% of the animals, and for 25 of the 43 OTU with a frequency between 10 and 25%. On a global scale, the Bayes factor revealed substantial evidence in favor of the genetic control of the number of observed OTU and Shannon indices. At the taxon-specific level, significant proportions of the OTU and relative abundances of genera were influenced by additive genetic, litter, and cage effects. Several members of the genera Bacteroides and Parabacteroides were strongly influenced by the host genetics and nursing environment, whereas the family S24-7 and the genus Ruminococcus were strongly influenced by cage effects. Conclusions: This study demonstrates that host genetics shapes the overall rabbit cecal microbial diversity and that a significant proportion of the taxa is influenced either by host genetics or environmental factors, such as litter and/or cage. © 2022, The Author(s)
Genome-wide association study for feed efficiency in collective cage-raised rabbits under full and restricted feeding
Feed efficiency (FE) is one of the most economically and environmentally relevant traits in the animal production sector. The objective of this study was to gain knowledge about the genetic control of FE in rabbits. To this end, GWASs were conducted for individual growth under two feeding regimes (full feeding and restricted) and FE traits collected from cage groups, using 114 604 autosome SNPs segregating in 438 rabbits. Two different models were implemented: (1) an animal model with a linear regression on each SNP allele for growth trait; and (2) a two‐trait animal model, jointly fitting the performance trait and each SNP allele content, for FE traits. This last modeling strategy is a new tool applied to GWAS and allows information to be considered from non‐genotyped individuals whose contribution is relevant in the group average traits. A total of 189 SNPs in 17 chromosomal regions were declared to be significantly associated with any of the five analyzed traits at a chromosome‐wide level. In 12 of these regions, 20 candidate genes were proposed to explain the variation of the analyzed traits, including genes such as FTO, NDUFAF6 and CEBPA previously associated with growth and FE traits in monogastric species. Candidate genes associated with behavioral patterns were also identified. Overall, our results can be considered as the foundation for future functional research to unravel the actual causal mutations regulating growth and FE in rabbits.info:eu-repo/semantics/publishedVersio
Civil society participation in international governance : the UN and the WTO compared
Civil society participation has become a buzzword in the debate about the legitimacy and accountability of international governance. Many organizations, prominently among them the World Trade Organization (WTO), have come under considerable pressure to open up their policy-making process towards non-state actors. Although the WTO has become more transparent in recent years, direct stakeholder access to its policy making is still denied. This situation is often contrasted with that at the United Nations (UN), where there is (allegedly) much more formally regulated and more substantial participation of civil society. In this paper, we compare the patterns of participation in these two organizations and seek to identify some common dynamics. We present a general framework for analysis based on a model of the policy cycle that allows us to distinguish ‘push’ and ‘pull’ factors that determine cooperation in different phases of policy making. In our empirical study, we find that in the WTO, there are few incentives for the organization itself to pull civil society actors into its policy-making process. Agendasetting is the task of governments; research and analysis is delivered by the Secretariat; compliance control is undertaken jointly by the organization and its members. To push the door to trade policy making open, civil society can only rely on public shaming, that is, threatening to undermine the organization’s legitimacy as it violates widely accepted standards of good governance. In the UN system, there is in fact more cooperation, but it remains largely limited to the policy phases of agenda-setting, research and analysis and compliance control. Quite like the WTO, the UN protects an intergovernmental core of policy making in which cooperation with civil society remains at the discretion of state parties. Evidence for this are informal and ad hoc ways of collaboration and a lack of participatory rights for non-state actors in the Security Council and the General Assembly. We conclude that studying civil society participation in international public organizations through the lens of the policy cycle can give us a fine-grained picture of cooperative arrangements and enables us to identify potentials for cooperation as well as exclusion. Yet, we also observed two other factors at work that were not really grasped by the model of the policy cycle. First, the institutional culture of organizations can be more or less amenable to civil society. Second, organizations are susceptible to campaigns for ‘good governance’ that invoke standards of due process and may open the door to nonstate actors
CP-odd static electromagnetic properties of the W gauge boson and the t quark via the anomalous tbW coupling
In the framework of the electroweak chiral Lagrangian, the one-loop induced
effects of the anomalous coupling, which includes both left- and
right-handed complex components, on the static electromagnetic properties of
the boson and the quark are studied. The attention is focused mainly on
the CP-violating electromagnetic properties. It is found that the
anomalous coupling can induce both CP-violating moments of the boson,
namely, its electric dipole () and magnetic quadrupole
() moments. As far as the quark is concerned, a potentially
large electric dipole moment can arise due to the anomalous
coupling. The most recent bounds on the left- and right-handed parameters from
meson physics lead to the following estimates e-cm and e-cm, which
are 7 and 14 orders of magnitude larger than the standard model (SM)
predictions, whereas may be as large as e-cm, which is about 8
orders of magnitude larger than its SM counterpart.Comment: This paper has been merged with hep-ph/0612171 for publication in
Physical Review
Origen y evolución magmática en la sierra Santa Catarina y el campo Milpa Alta, cinturón volcánico mexicano central
LiLO: Lightweight and low-bias LiDAR Odometry method based on spherical range image filtering
In unstructured outdoor environments, robotics requires accurate and
efficient odometry with low computational time. Existing low-bias LiDAR
odometry methods are often computationally expensive. To address this problem,
we present a lightweight LiDAR odometry method that converts unorganized point
cloud data into a spherical range image (SRI) and filters out surface, edge,
and ground features in the image plane. This substantially reduces computation
time and the required features for odometry estimation in LOAM-based
algorithms. Our odometry estimation method does not rely on global maps or loop
closure algorithms, which further reduces computational costs. Experimental
results generate a translation and rotation error of 0.86\% and 0.0036{\deg}/m
on the KITTI dataset with an average runtime of 78ms. In addition, we tested
the method with our data, obtaining an average closed-loop error of 0.8m and a
runtime of 27ms over eight loops covering 3.5Km.Comment: This paper is under review at the journal "Autonomous Robots"
(Springer
Breeding farm, level of feeding and presence of antibiotics in the feed influence rabbit cecal microbiota
Background
The effect of the production environment and different management practices in rabbit cecal microbiota remains poorly understood. While previous studies have proved the impact of the age or the feed composition, research in the breeding farm and other animal management aspects, such as the presence of antibiotics in the feed or the level of feeding, is still needed. Characterization of microbial diversity and composition of growing rabbits raised under different conditions could help better understand the role these practices play in cecal microbial communities and how it may result in different animal performance.
Results
Four hundred twenty-five meat rabbits raised in two different facilities, fed under two feeding regimes (ad libitum or restricted) with feed supplemented or free of antibiotics, were selected for this study. A 16S rRNA gene-based assessment through the MiSeq Illumina sequencing platform was performed on cecal samples collected from these individuals at slaughter. Different univariate and multivariate approaches were conducted to unravel the influence of the different factors on microbial alpha diversity and composition at phylum, genus and OTU taxonomic levels. The animals raised in the facility harboring the most stable environmental conditions had greater, and less variable, microbial richness and diversity. Bootstrap univariate analyses of variance and sparse partial least squares-discriminant analyses endorsed that farm conditions exerted an important influence on rabbit microbiota since the relative abundances of many taxa were found differentially represented between both facilities at all taxonomic levels characterized. Furthermore, only five OTUs were needed to achieve a perfect classification of samples according to the facility where animals were raised. The level of feeding and the presence of antibiotics did not modify the global alpha diversity but had an impact on some bacteria relative abundances, albeit in a small number of taxa compared with farm, which is consistent with the lower sample classification power according to these factors achieved using microbial information.
Conclusions
This study reveals that factors associated with the farm effect and other management factors, such as the presence of antibiotics in the diet or the feeding level, modify cecal microbial communities. It highlights the importance of offering a controlled breeding environment that reduces differences in microbial cecal composition that could be responsible for different animal performance.info:eu-repo/semantics/publishedVersio
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