1,797 research outputs found
Effects of synbiotic supplement on human gut microbiota, body composition and weight loss in obesity
Targeting gut microbiota with synbiotics (probiotic supplements containing prebiotic components) is emerging as a promising intervention in the comprehensive nutritional approach to reducing obesity. Weight loss resulting from low-carbohydrate high-protein diets can be significant but has also been linked to potentially negative health effects due to increased bacterial fermentation of undigested protein within the colon and subsequent changes in gut microbiota composition. Correcting obesity-induced disruption of gut microbiota with synbiotics can be more effective than supplementation with probiotics alone because prebiotic components of synbiotics support the growth and survival of positive bacteria therein. The purpose of this placebo-controlled intervention clinical trial was to evaluate the effects of a synbiotic supplement on the composition, richness and diversity of gut microbiota and associations of microbial species with body composition parameters and biomarkers of obesity in human subjects participating in a weight loss program. The probiotic component of the synbiotic used in the study contained Lactobacillus acidophilus, Bifidobacterium lactis, Bifidobacterium longum, and Bifidobacterium bifidum and the prebiotic component was a galactooligosaccharide mixture. The results showed no statistically significant differences in body composition (body mass, BMI, body fat mass, body fat percentage, body lean mass, and bone mineral content) between the placebo and synbiotic groups at the end of the clinical trial (3-month intervention, 20 human subjects participating in weight loss intervention based on a low-carbohydrate, high-protein, reduced energy diet). Synbiotic supplementation increased the abundance of gut bacteria associated with positive health effects, especially Bifidobacterium and Lactobacillus, and it also appeared to increase the gut microbiota richness. A decreasing trend in the gut microbiota diversity in the placebo and synbiotic groups was observed at the end of trial, which may imply the effect of the high-protein low-carbohydrate diet used in the weight loss program. Regression analysis performed to correlate abundance of species following supplementation with body composition parameters and biomarkers of obesity found an association between a decrease over time in blood glucose and an increase in Lactobacillus abundance, particularly in the synbiotic group. However, the decrease over time in body mass, BMI, waist circumstance, and body fat mass was associated with a decrease in Bifidobacterium abundance. The results obtained support the conclusion that synbiotic supplement used in this clinical trial modulates human gut microbiota by increasing abundance of potentially beneficial microbial species
The backbone of democracy. The metainstitutional basis of modern society
The article deals with the "minimal configuration" of social institutions that ensure sustainable development not by adapting to the environment (the adaptive behaviour characteristic of traditional societies), but through uninterrupted generation and implementation of innovations that transform environment to meet the changing needs of humankind. This type of active adaptive behaviour characteristic of modern society could not be maintained in the absence of three basic "metainstitutions" of modernity, viz. 1) science, 2) the banking and exchange system, 3) institutions of representative democracy (parliaments), plus three "support institutions": 4) free press (mass media), 5) rational bureaucracy, 6) independent judiciaryyesBelgorod State National Research Universit
Superanalogs of the Calogero operators and Jack polynomials
A depending on a complex parameter superanalog
of Calogero operator is constructed; it is related with the root system of the
Lie superalgebra . For we obtain the usual Calogero
operator; for we obtain, up to a change of indeterminates and parameter
the operator constructed by Veselov, Chalykh and Feigin [2,3]. For the operator is the radial part of the 2nd
order Laplace operator for the symmetric superspaces corresponding to pairs
and , respectively. We will show
that for the generic and the superanalogs of the Jack polynomials
constructed by Kerov, Okunkov and Olshanskii [5] are eigenfunctions of
; for they coinside with the spherical
functions corresponding to the above mentioned symmetric superspaces. We also
study the inner product induced by Berezin's integral on these superspaces
Casimir eigenvalues for universal Lie algebra
For two different natural definitions of Casimir operators for simple Lie
algebras we show that their eigenvalues in the adjoint representation can be
expressed polynomially in the universal Vogel's parameters and give explicit formulae for the generating functions of these
eigenvalues.Comment: Slightly revised versio
Generalized Calogero-Moser systems from rational Cherednik algebras
We consider ideals of polynomials vanishing on the W-orbits of the
intersections of mirrors of a finite reflection group W. We determine all such
ideals which are invariant under the action of the corresponding rational
Cherednik algebra hence form submodules in the polynomial module. We show that
a quantum integrable system can be defined for every such ideal for a real
reflection group W. This leads to known and new integrable systems of
Calogero-Moser type which we explicitly specify. In the case of classical
Coxeter groups we also obtain generalized Calogero-Moser systems with added
quadratic potential.Comment: 36 pages; the main change is an improvement of section 7 so that it
now deals with an arbitrary complex reflection group; Selecta Math, 201
Elucidating the structural composition of a Fe-N-C catalyst by nuclear and electron resonance techniques
Fe–N–C catalysts are very promising materials for fuel cells and metal–air batteries. This work gives fundamental insights into the structural composition of an Fe–N–C catalyst and highlights the importance of an in‐depth characterization. By nuclear‐ and electron‐resonance techniques, we are able to show that even after mild pyrolysis and acid leaching, the catalyst contains considerable fractions of α‐iron and, surprisingly, iron oxide. Our work makes it questionable to what extent FeN4 sites can be present in Fe–N–C catalysts prepared by pyrolysis at 900 °C and above. The simulation of the iron partial density of phonon states enables the identification of three FeN4 species in our catalyst, one of them comprising a sixfold coordination with end‐on bonded oxygen as one of the axial ligands
Thermodynamic properties of methyl 4-(4-methoxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate in organic solutions
The enthalpy and the entropy of dissolution of methyl 4-(4-methoxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate in 2-propanol, ethyl acetate, acetonitrile, 2-propanone and benzene were determined from the temperature dependence of its solubility.The enthalpies and the entropies of mixing at 298 K were calculated taking into account the enthalpy of melting of the compound, determined via differential thermal analysis.The influence of the solvent on the solubility of the compound and on the corresponding enthalpy and entropy of mixing values was shown
A theoretical model of a wake of a body towed in a stratified fluid at large Reynolds and Froude numbers
International audienceThe objective of the present paper is to develop a theoretical model describing the evolution of a turbulent wake behind a towed sphere in a stably stratified fluid at large Froude and Reynolds numbers. The wake flow is considered as a quasi two-dimensional (2-D) turbulent jet flow whose dynamics is governed by the momentum transfer from the mean flow to a quasi-2-D sinuous mode growing due to hydrodynamic instability. The model employs a quasi-linear approximation to describe this momentum transfer. The model scaling coefficients are defined with the use of available experimental data, and the performance of the model is verified by comparison with the results of a direct numerical simulation of a 2-D turbulent jet flow. The model prediction for the temporal development of the wake axis mean velocity is found to be in good agreement with the experimental data obtained by Spedding (1997)
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