Bibliografie tematiche / Gluons

Indice

Articoli di riviste
Tesi
Libri
Capitoli di libri
Atti di convegni
Rapporti di organizzazioni

Letteratura scientifica selezionata sul tema "Gluons"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 6 settembre 2023

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili

Scegli il tipo di fonte:

Consulta la lista di attuali articoli, libri, tesi, atti di convegni e altre fonti scientifiche attinenti al tema "Gluons".

Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.

Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.

Articoli di riviste sul tema "Gluons"

Wolschin, Georg. "Aspects of Relativistic Heavy-Ion Collisions". Universe 6, n. 5 (30 aprile 2020): 61. http://dx.doi.org/10.3390/universe6050061.

Testo completo

Abstract (sommario):

The rapid thermalization of quarks and gluons in the initial stages of relativistic heavy-ion collisions is treated using analytic solutions of a nonlinear diffusion equation with schematic initial conditions, and for gluons with boundary conditions at the singularity. On a similarly short time scale of t ≤ 1 fm/c, the stopping of baryons is accounted for through a QCD-inspired approach based on the parton distribution functions of valence quarks, and gluons. Charged-hadron production is considered phenomenologically using a linear relativistic diffusion model with two fragmentation sources, and a central gluonic source that rises with ln 3 ( s N N ) . The limiting-fragmentation conjecture that agrees with data at energies reached at the Relativistic Heavy-Ion Collider (RHIC) is found to be consistent with Large Hadron Collider (LHC) data for Pb-Pb at s N N = 2.76 and 5.02 TeV. Quarkonia are used as hard probes for the properties of the quark-gluon plasma (QGP) through a comparison of theoretical predictions with recent CMS, ALICE and LHCb data for Pb-Pb and p-Pb collisions.

Gli stili APA, Harvard, Vancouver, ISO e altri

GEORGIOU, GEORGE, e GEORGE SAVVIDY. "PRODUCTION OF NON-ABELIAN TENSOR GAUGE BOSONS TREE AMPLITUDES AND BCFW RECURSION RELATION". International Journal of Modern Physics A 26, n. 15 (20 giugno 2011): 2537–55. http://dx.doi.org/10.1142/s0217751x1105350x.

Testo completo

Abstract (sommario):

The BCFW recursion relation is used to calculate tree-level scattering amplitudes in generalized Yang–Mills theory and, in particular, four-particle amplitudes for the production rate of non-Abelian tensor gauge bosons of arbitrary high spin in the fusion of two gluons. The consistency of the calculations in different kinematical channels is fulfilled when all dimensionless cubic coupling constants between vector bosons and high spin non-Abelian tensor gauge bosons are equal to the Yang–Mills coupling constant. We derive a generalization of the Parke–Taylor formula in the case of production of two tensor gauge bosons of spin-s and N gluons (jets). The expression is holomorphic in the spinor variables of the scattered particles, exactly as the MHV gluon amplitude is, and reduces to the gluonic MHV amplitude when s = 1.

Gli stili APA, Harvard, Vancouver, ISO e altri

Cho, Y. M. "Abelian Decomposition and Monopole Condensation in QCD". EPJ Web of Conferences 182 (2018): 02029. http://dx.doi.org/10.1051/epjconf/201818202029.

Testo completo

Abstract (sommario):

We demonstrate the monopole condensation in QCD using the Abelian decomposition. The Abelian decomposition decomposes the gluons to the color neutral binding gluons (the neurons and the monopoles) and the colored valence gluons (the chromons), and shows that QCD can be viewed as the restricted QCD (RCD) made of the binding gluons which has the chromons as colored source. This simplifies the QCD dynamics greatly. In the perturbative regime this decomposes the gluon propagater to the neuron propagaters and the chromon propagaters, and simplifies the Feynman diagram. In the non-perturbative regime this allows us to calculate the QCD effective potential gauge independently, and demonstrate the monopole condensation unambiguously.

Gli stili APA, Harvard, Vancouver, ISO e altri

NISHIJIMA, KAZUHIKO. "CONFINEMENT OF QUARKS AND GLUONS". International Journal of Modern Physics A 09, n. 21 (20 agosto 1994): 3799–819. http://dx.doi.org/10.1142/s0217751x94001539.

Testo completo

Abstract (sommario):

It is proved without recourse to any approximation that quarks and gluons are confined simultaneously when the anomalous dimension of the gluon field is negative in the weak coupling limit. The proof is based on the BRS invariance of quantum chromodynamics and the Oehme–Zimmermann superconvergence relation for the spectral function of the gluon field.

Gli stili APA, Harvard, Vancouver, ISO e altri

Morreale, Astrid, e Farid Salazar. "Mining for Gluon Saturation at Colliders". Universe 7, n. 8 (23 agosto 2021): 312. http://dx.doi.org/10.3390/universe7080312.

Testo completo

Abstract (sommario):

Quantum chromodynamics (QCD) is the theory of strong interactions of quarks and gluons collectively called partons, the basic constituents of all nuclear matter. Its non-abelian character manifests in nature in the form of two remarkable properties: color confinement and asymptotic freedom. At high energies, perturbation theory can result in the growth and dominance of very gluon densities at small-x. If left uncontrolled, this growth can result in gluons eternally growing violating a number of mathematical bounds. The resolution to this problem lies by balancing gluon emissions by recombinating gluons at high energies: phenomena of gluon saturation. High energy nuclear and particle physics experiments have spent the past decades quantifying the structure of protons and nuclei in terms of their fundamental constituents confirming predicted extraordinary behavior of matter at extreme density and pressure conditions. In the process they have also measured seemingly unexpected phenomena. We will give a state of the art review of the underlying theoretical and experimental tools and measurements pertinent to gluon saturation physics. We will argue for the need of high energy electron-proton/ion colliders such as the proposed EIC (USA) and LHeC (Europe) to consolidate our knowledge of QCD knowledge in the small x kinematic domains.

Gli stili APA, Harvard, Vancouver, ISO e altri

Peláez, Marcela. "Massive gluons in Curci-Ferrari model for describing infrared QCD". EPJ Web of Conferences 274 (2022): 02002. http://dx.doi.org/10.1051/epjconf/202227402002.

Testo completo

Abstract (sommario):

At large energy quarks and gluons behave as free particles and therefore the standard perturbative analysis of QCD gives very good results. However, this is not the situation in the low energy regime of QCD which is generally treated with nonperturbative methods. In spite of this, lattice simulations observe that the expansion parameter is not large in the gluonic sector. In particular, the coupling constant do not reach a Landau pole in the infrared as it is expected by standard perturbation theory. On top of this, lattice simulations find that the gluon propagator behaves as a massive propagator in the infrared. Motivated by these observations we use a model that includes a mass for the gluon (Curci-Ferrari) that can reproduce the same kind of behaviour for the gluon propagator and also a similar expansion parameter as the one found by the lattice. In this proceeding we show some of the results of quenched correlation functions obtained by using that small parameter for computing one and two loops corrections. At the end, we compare them with lattice data obtaining very good results.

Gli stili APA, Harvard, Vancouver, ISO e altri

Kokoulina, Elena, Andrey Kutov, Vladimir Nikitin, Vasilii Riadovikov e Alexander Vorobiev. "A look at hadronization via high multiplicity". EPJ Web of Conferences 204 (2019): 06009. http://dx.doi.org/10.1051/epjconf/201920406009.

Testo completo

Abstract (sommario):

Multiparticle production is studied experimentally and theoretically in QCD that describes interactions in the language of quarks and gluons. In the experiment the real hadrons are registered. Various phenomenological models are used for transfer from quarks and gluons to observed hadrons. In order to describe the high multiplicity region, we have developed a gluon dominance model (GDM). It represents a convolution of two stages. The first stage is described as a part of QCD. For the second one (hadronization), the phenomenological model is used. To describe hadronization, a scheme has been proposed, consistent with the experimental data in the region of its dominance. Comparison of this model with data on e+e- annihilation over a wide energy interval (up to 200 GeV) has confirmed the fragmentation mechanism of hadronization, the development of the quark-gluon cascade with energy increase and domination of bremsstrahlung gluons. The description of topological cross sections in pp collisions within GDM testifies that in hadron collisions the mechanism of hadronization is being replaced by the recombination one. At that point, gluons play an active role in the multiparticle production process, and valence quarks are passive. They stay in the leading particles, and only the gluon splitting is responsible for the region of high multiplicity. GDM with inclusion of intermediate quark charged topologies describes topological cross sections in pp̅ annihilation and explains initial linear growth in the region of negative values of a secondary correlative momentum vs average pion multiplicity with increasing of energy. The proposed hadronization scheme can describe the basic processes of multiparticle production.

Gli stili APA, Harvard, Vancouver, ISO e altri

MARTYNOV, M. V., e A. D. SMIRNOV. "COLORED SCALAR PARTICLES PRODUCTION IN pp-COLLISIONS AND POSSIBLE MASS LIMITS FOR SCALAR GLUONS FROM FUTURE LHC DATA". Modern Physics Letters A 23, n. 34 (10 novembre 2008): 2907–13. http://dx.doi.org/10.1142/s0217732308028375.

Testo completo

Abstract (sommario):

Cross sections of the colored scalar particle production in pp-collisions are calculated and differential and total cross sections of the corresponding parton subprocesses are obtained. The total cross section of scalar gluon production in pp-collisions at the LHC is estimated and the dominant decays of scalar gluons are discussed. The production cross section of scalar gluons F with masses mF ≲ 1300 GeV is shown to be sufficient for the effective production of these particles at the LHC.

Gli stili APA, Harvard, Vancouver, ISO e altri

da SILVA, MÁRIO L. L., CÉSAR A. Z. VASCONCELLOS e DIMITER HADJIMICHEF. "A NEW SIGNATURE FOR GLUEBALLS". International Journal of Modern Physics D 13, n. 07 (agosto 2004): 1399–404. http://dx.doi.org/10.1142/s0218271804005596.

Testo completo

Abstract (sommario):

In this work we use a mapping technique to derive in the context of a constituent gluon model an effective Hamiltonian that involves explicit gluon degrees of freedom. We study glueballs with two gluons using the Fock–Tani formalism.

Gli stili APA, Harvard, Vancouver, ISO e altri

Zolghadr, Behnam. "Being and Nothingness". Australasian Journal of Logic 16, n. 3 (26 giugno 2019): 68. http://dx.doi.org/10.26686/ajl.v16i3.4075.

Testo completo

Abstract (sommario):

Graham Priest’s Theory of Gluons concerns the problem of unity, i.e. what makes an object into a unity? Based on his theory of Gluons, Priest gives his accounts of being and nothingness. In this paper, I will explore the relationship between nothingness and the being of the totality of every object, and then, I will try to demonstrate that, according to Gluon Theory, these two have the same properties, or in other words, nothingness is the being of the totality of every object.

Gli stili APA, Harvard, Vancouver, ISO e altri

Più fonti

Tesi sul tema "Gluons"

Franzon, Bruno Cezar de Souza. "Gluons em estrelas de nêutrons". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-02082012-131729/.

Testo completo

Abstract (sommario):

O plasma de quarks e gluons (QGP) em temperatura zero e alta densidade bariônica é um sistema que pode existir no interior de estrelas densas. É possível que esse QGP frio compartilhe algumas características com o plasma quente, observado em colisões de íons pesados relativísticos, sendo também um sistema fortemente interagente. Neste trabalho, utilizamos uma equação de estado derivada a partir da QCD e a aplicamos no estudo de estrutura estelar. Mostramos que nossos resultados são compatíveis com o pulsar PSR J1614 2230 de massa (1.97 ± 0.04)M.
The Quark Gluon Plasma (QGP) at zero temperature and high baryon number is a system that may exist in the core of dense stars. This cold QGP has a rich phase structure and at high enough chemical potential it is quite possible that it shares some features with the hot QGP observed in heavy ion collisions, being also a strongly interacting system. We use an equation of state derived from QCD and apply it to study of stellar structure. Our results reproduce the measured mass, (1.97 ± 0.04)M, of the pulsar PSR J1614 2230.

Gli stili APA, Harvard, Vancouver, ISO e altri

Angeles, Martinez Rene. "Coulomb gluons and the ordering variable". Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/coulomb-gluons-and-the-ordering-variable(c9d90246-4afa-4647-aece-bdd9605b7692).html.

Testo completo

Abstract (sommario):

In this thesis, we study the soft gluon corrections to hard wide-angle scattering processes due to a virtual gluon exchange (one-loop order) and the emission of up to two gluons. Our primary aim is to determine the ordering condition that should be used to dress a hard scattering process with corrections due to gluon emissions and a Coulomb (Glauber) gluon exchange. We find that, due to an elegant cancellation of many Feynman diagrams, a specific ordering variable should be used to order the transverse momentum of the exchanged Coulomb gluon with respect to the real emissions. Furthermore, in the case of the scattering process accompanied with a single emission, we find that the radiative part of the loop correction satisfies the same ordering condition as the Coulomb gluon contribution. Based upon the assumption that the ordering condition continues at higher orders, we conjecture an expression for the soft corrections to a general hard scattering process due to one-loop and any number of gluon emissions.

Gli stili APA, Harvard, Vancouver, ISO e altri

Wormsbecher, Wadim. "On Relations between Gluons and Gravitons". Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/20658.

Testo completo

Abstract (sommario):

Wir behandeln einige Spezialfälle von Beziehungen zwischen Eich- und Gravitationstheorien. Wir setzen den Schwerpunkt auf Baumlevelstreuamplituden in Einstein-(Skalar-)-Chromo-Dynamik, welche Streuungen zwischen Gluonen, massiven fundamentalen Quarks (Skalaren) und Gravitonen beschreibt. Wir untersuchen den endlichen Anteil von reiner Gluonenstreuung mit zwei kollinearen Gluonen. Basierend auf einem Vorschlag von S. Stieberger und T. Taylor, stehen diese in Beziehung zu Steuamplituden in Einstein-Yang-Mills Theorie, in welchen die kollinearen Gluonen durch ein Graviton ersetzt werden. Wir führen einen Beweis dieser Beziehungen unter der Ausnutzung des Cachazo-He-Yuan Formalismus durch. Parallel dazu werden wir einen Einblick in mysteriöse Wechselwirkunen dieser Beziehungen mit Eichinvarianzverletzungen des kollinearen Gluon Grenzwertes von Yang-Mills Streuampliuden geben. Danach behandeln wir eine andere Art von linearen Beziehungen zwischen Streuamplituden in Yang-Mills Theorie und Einstein-Yang-Mills Theorie, welche ebenfalls von S. Stieberger und T. Taylor vorgeschlagen wurden und direkt einzelne Gluonen mit einzelnen Gravitonen verbinden. Wir beweisen die Universalität dieser Beziehungen, in Anwesenheit von fundamental geladenen und massiven Fermionen und Skalaren. Schliesslich formulieren wir eine neue Zweifachkopiebeziehung zwischen klassisch effektiven Wirkungen. Die effektive Wirkung eines Systems von farblich geladenen, massiven und klassischen Weltlinien, welche über Yang-Mills wechselwirken, wird mit einem System von dilatonisch geladenen, massiven und klassischen Weltlinien, welche über Dilatongravitation wechselwirken, in Verbindung gesetzt. Somit verbessern wir eine, aus dem Kontext von Lösungen zu störungstheoretischen Bewegungsgleichungen, sowohl für das Gluon als auch für das Graviton, derselben Systeme, bekannte Zweifachkopievorschrift, formuliert von W. Goldberger und A. Ridgway.
We analyze several cases of mysterious connections between gauge and gravity theories, known as double copy relations. We focus on tree level scattering amplitudes in Einstein-(scalar-)-chromo-dynamics, i.e. scattering scenarios between gluons, massive fundamental quarks (scalars) and gravitons. In these scenarios we study the sub leading contribution to the adjacent collinear gluon limits in pure Yang-Mills amplitudes. Recently, S. Stieberger and T. Taylor have proposed a linear combination of amplitudes with a pair of collinear gluons to an Einstein-Yang-Mills amplitude. We present a proof of such relations using a novel representation of bosonic tree level amplitudes based on a localized integral on the Riemann sphere, called the Cachazo-He-Yuan formalism. Moreover, we give insight into an intriguing interplay between those relations and surprising gauge invariance violations of the sub-leading collinear gluon limit of Yang-Mills amplitudes. Next, we will focus on yet another set of relations between Yang-Mills amplitudes and Einstein-Yang-Mills amplitudes that were also proposed by S. Stieberger and T. Taylor. They directly relate single gluons to single gravitons. We show universality of such relations, i.e. their validity in the presence of massive fundamental quarks and scalars. For that purpose, we will use a Feynman diagrammatic approach which results in a novel color-to-kinematics rule, mapping gluons to gravitons in these scattering scenarios. Finally, we establish a novel double copy connection between classical effective actions of two massive classical worldlines which are colored and interacting in Yang-Mills theory and dilaton charged and interacting through dilaton-gravity. Doing so, we extend and improve existing work relating the same system of worldlines through a double copy at the level of perturbative solutions to the involved equations of motion for the gluon and graviton fields, as has been proposed by W. Goldberger and A. Ridgway.

Gli stili APA, Harvard, Vancouver, ISO e altri

Cazaroto, Erike Roberto. "A saturação de gluons em futuros aceleradores". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-12032013-132708/.

Testo completo

Abstract (sommario):

Neste trabalho nós fazemos predições para o comportamento de grandezas observáveis a serem medidas nos futuros aceleradores de partículas e também no LHC. Nós estudamos três processos: elétron-núcleo (eA), fóton-fóton e próton-núcleo (pA). Nos processos eA nós calculamos as seções de choque de produção de mésons vetoriais e de fótons reais usando os modelos de saturação rcBK e b-CGC. Nós verificamos que apenas a produção de mésons pesados poderá nos dizer qual destes dois modelos é o mais correto para descrever a seção de choque dipolo-próton. No estudo dos processos fóton-fóton nós calculamos as seções de choque de espalhamento e a função de estrutura do fóton. Nós propomos um novo modelo de saturação para a interação entre dois dipolos de cor e comparamos suas predições com aquelas de um modelo disponível na literatura para esta interação. Nós verificamos que o nosso modelo prediz um crescimento bem menos acentuado para os observáveis calculados do que prediz o outro modelo. No último processo que estudamos, a colisão pA, nós calculamos as seções de choque de produção de charme e de bottom nas energias do LHC. Nós verificamos que os dados sobre a produção de charme serão os mais promissores na identificação de sinais de física de saturação. Nós também verificamos que o efeito de shadowing nuclear causa uma diminuição considerável na seção de choque de produção de charme, o que indica que este observável poderá ser útil na determinação da magnitude deste efeito. Por outro lado, apenas a seção de choque de produção de bottom apresenta o efeito de antishadowing.
In this thesis we make predictions for the behavior of observables that will be measured in future particle colliders and also at the LHC. We address three different types of collisions: electron-ion (eA), photon-photon and proton-nucleus (pA). For eA processes we calculate the vector meson and real photon production cross section using the saturation models rcBK and b-CGC. We observe that only the production of heavy mesons will be useful to determine which saturation model correctly describes the dipole-proton interaction. For the photon-photon process we calculate the total cross section as well as the photon structure function. We propose a new saturation model for the interaction between two color dipoles and we compare its predictions with those of other models available in the literature. We observe that our model predicts a much smoother growth of the observables than the other models. As for pA collisions, we calculate the cross section of charm and bottom production at LHC energies. We observe that charm production is very sensitive to saturation effects as well as to nuclear shadowing effects. Therefore, this observable can be useful to determine the dynamics of QCD at high energies, as well as the magnitude of the shadowing. On the other hand, only the bottom production cross section is sensitive to antishadowing effect.

Gli stili APA, Harvard, Vancouver, ISO e altri

Isert, Dagmar Sigrun. "Transport theory for scalar quarks and gluons". [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=961877200.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Kubelskyi, Oleksandr. "Gluons and the spin of the proton". Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-125564.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Silva, Paulo Sérgio Rodrigues da [UNESP]. "Conseqüências fenomenológicas de um propagador de gluons com massa dinâmica". Universidade Estadual Paulista (UNESP), 1998. http://hdl.handle.net/11449/102520.

Testo completo

Abstract (sommario):

Made available in DSpace on 2014-06-11T19:32:10Z (GMT). No. of bitstreams: 0 Previous issue date: 1998-08Bitstream added on 2014-06-13T20:07:50Z : No. of bitstreams: 1 silva_psr_dr_ift.pdf: 978323 bytes, checksum: f2a70069a3da35e7d430df26a1778d76 (MD5)
São analisados as consequências de um comportamento finito no infravermelho para certos propagadores de gluons discutidos na literatura. Três problemas distintos são estudados: o cálculo da constante de acoplamento crítico que leva à transição quiral à comparação entre as fenomelogias do Pomeron e de quebra dinâmica de simetria quiral e o cálculo do potencial efetivo para operadores compostos na QCD puramente gluônica. Os resultados obtidos mostram como dados fenomenológicos podem auxiliar a mapear o comportamento do propagador do gluon na região infravermelha.
Abstracts: The consequences of an infrared finite behavior of some gluon propagators are examined. Three distint problems are studied: the computation of the critical coupling constant which leads to chiral transition the confrontation between the Pomeron and dynamical chiral symmetry breawing phenomenologies and the calculation of the efective potential for composite operators in the purel gluonic QCD. The results show how phenomenological data can aid to trace the gluon propagator behavior in the infrared.

Gli stili APA, Harvard, Vancouver, ISO e altri

Silva, Paulo Sérgio Rodrigues da. "Conseqüências fenomenológicas de um propagador de gluons com massa dinâmica /". São Paulo : [s.n.], 1998. http://hdl.handle.net/11449/102520.

Testo completo

Abstract (sommario):

Orientador: Adriano Antônio Natale
Resumo: São analisados as consequências de um comportamento finito no infravermelho para certos propagadores de gluons discutidos na literatura. Três problemas distintos são estudados: o cálculo da constante de acoplamento crítico que leva à transição quiral à comparação entre as fenomelogias do Pomeron e de quebra dinâmica de simetria quiral e o cálculo do potencial efetivo para operadores compostos na QCD puramente gluônica. Os resultados obtidos mostram como dados fenomenológicos podem auxiliar a mapear o comportamento do propagador do gluon na região infravermelha.
Abstracts: The consequences of an infrared finite behavior of some gluon propagators are examined. Three distint problems are studied: the computation of the critical coupling constant which leads to chiral transition the confrontation between the Pomeron and dynamical chiral symmetry breawing phenomenologies and the calculation of the efective potential for composite operators in the purel gluonic QCD. The results show how phenomenological data can aid to trace the gluon propagator behavior in the infrared.
Doutor

Gli stili APA, Harvard, Vancouver, ISO e altri

Ziaeepour, Houri. "Contribution a l'étude des possibilités de mesurer les fonctions de structures à HERA avec H1". Paris 7, 1989. http://www.theses.fr/1989PA077127.

Testo completo

Abstract (sommario):

Il s'agit d'une étude des possibilités du détecteur H1 de mesurer à HERA, les fonctions de structure, notamment celles des gluons. Nous avons d'abord étudié le domaine cinématique accessible ; c'est à dire celui où l'on peut acquérir suffisamment d'événements, sans être noyé par le bruit de fond, et les reconstruire avec assez de précision à partir des particules observées. Notons que ceci a conduit à suggérer, pour le déclenchement sur les traces émises vers l'avant, d'exiger l'identification d'au moins deux trajectoires. Nous avons ensuite étudier les moyens d'extraire des données la fonction de structure des gluons, soit en considérant sa contribution dans l'équation d'Altarelli-Parisi, soit directement en sélectionnant différents types d'événements. Les résultats s'avèrent très sensibles au modèle utilisé et aux corrections d'ordre supérieur de QCD, notamment aux petites valeurs de x. Nous avons cependant, dans le cas de QCD au premier ordre, développé une méthode semi-analytique tenant compte de l'existence d'un quark massif.

Gli stili APA, Harvard, Vancouver, ISO e altri

Roy, Christelle. "L'Etrangeté du Plasma de Quarks et de Gluons". Habilitation à diriger des recherches, Université de Nantes, 2005. http://tel.archives-ouvertes.fr/tel-00011076.

Testo completo

Abstract (sommario):

A l'instar des trois autres expériences auprès du collisionneur RHIC (Relativistic Heavy Ion Collider) du Brookhaven National Laboratory près de New York, STAR (Solenoidal Tracker At RHIC) est entièrement consacrée à la mise en évidence de cet état particulier de la matière nucléaire prédit par les calculs de QCD (Quantum ChromoDynamics) sur réseau : le plasma de quarks et de gluons (QGP pour Quark Gluon Plasma). Cet état, supposé être celui de l'Univers quelques fractions de secondes après le Big Bang, consisterait d'après sa définition originelle de 1975, en une matière dans laquelle quarks et gluons seraient déconfinés, sans interaction. Il pourrait être créé en laboratoire lors de collisions d'ions lourds réalisées à des énergies ultra-relativistes afin d'atteindre des températures et densités d'énergie extrêmes.
Après quasiment 20 ans de recherche auprès des différents accélérateurs de particules américains et européens, le CERN annonce le 10 février 2000 au cours d'une conférence de presse, la mise en évidence expérimentale d'un état particulier de la matière nucléaire, compatible avec la formation d'un QGP, sans pouvoir toutefois le caractériser pleinement. Les expériences du RHIC ont alors pris le relais. Aujourd'hui, au travers une pléthore de résultats nouveaux et parfois bien surprenants, il apparaît de façon de plus en plus certaine, qu'effectivement un état atypique de matière nucléaire a été créé à RHIC et notre vision du QGP comme un gaz parfait de partons n'interagissant que très faiblement, a depuis changé. Un nouvel acronyme a été défini : sQGP pour Strongly Interacting QGP.
Pour parvenir à cette observation, il a fallu passer par la caractérisation même de l'évolution des collisions d'ions lourds, du point de vue chimique et dynamique, en comparant les phénomènes des collisions d'ions lourds pour lesquelles les conditions devraient être réunies pour former un QGP à des collisions d'énergies moindres ou de systèmes plus légers qui ne peuvent permettre cette formation. Le QGP est en effet produit de manière beaucoup trop furtive pour pouvoir le sonder directement. Mon mémoire d'Habilitation à Diriger des Recherches présente les résultats des analyses que j'ai menées et qui ont contribué à la mise en évidence de la formation d'un état nouveau au RHIC et à cette nouvelle vision du plasma. Les stigmates du QGP ont été recherchés avec les particules contenant des quarks étranges : les résonances de particules simplement étranges et les baryons doublement étranges.
La production des résonances étranges Lambda(1520) apporte en effet des informations sur la phase d'hadronisation du plasma (lorsque les partons se recomposent en hadrons) : selon leur observation ou non, il pourrait être possible de caractériser le freeze-out chimique (instant où les interactions inélastiques cessent et la composition chimique du système est figée), le freeze-out cinétique (instant où les interactions élastiques cessent et les particules n'interagissent plus), si ces deux freeze-out coïncident ou si, au contraire ils sont séparés dans le temps et de combien. L'idée est la suivante : les Lambdas(1520) se désintègrent quasiment instantanément en un proton et un kaon. Par conséquent, si le temps entre les freeze-out chimique et cinétique est long, les produits de désintégration de ces particules peuvent être absorbés dans le milieu dense qui a été créé. En revanche, si les deux freeze-out coïncident ou sont très proches, les produits de désintégration ne sont pas affectés et la particule mère, c'est-à-dire la résonance, peut être identifiée. Ainsi, en mesurant les taux de production de ces particules dans les collisions proton–proton pour lesquelles les deux freeze-out coïncident, et en comparant les taux obtenus dans les collisions Au–Au, à l'énergie nominale du RHIC, il est apparu qu'effectivement, au moins 4 fm/c séparent les deux freeze-out dans les collisions Au–Au. Cette conclusion constitue une étape importante dans la compréhension des collisions d'ions lourds ultra-relativistes et du comportement de la matière dans des conditions extrêmes. Cette analyse est apparue comme originale au sein de la collaboration STAR, étant la première étude sur les résonances étranges. Des algorithmes spécifiques ont dû être mis au point et sont largement utilisés au sein de la collaboration qui depuis étudie de nombreuses autres résonances ou recherche des objets plus exotiques.
La production des baryons étranges a été largement investiguée les années passées car une augmentation « anormale » des taux de production est attendue si un QGP est formé. Les expériences du CERN ont observé effectivement une surproduction de l'étrangeté dans les collisions Pb–Pb mais n'ont pu conclure de manière décisive quant à une formation éventuelle d'un plasma car ces résultats pouvaient être également reproduits par des modèles de gaz de hadrons. Nous avons mené une analyse similaire avec les données de STAR en comparant les taux de production des Xi, baryons doublement étranges, dans les collisions proton–proton et Au–Au à sqrt(s_NN) = 200 GeV. Là aussi, les résultats sont demeurés ambigus. Ainsi, ces résultats ont conduit un certain nombre de physiciens à ne plus considérer les taux de production de particules étranges comme une signature robuste de la formation d'un QGP. En revanche, l'étrangeté est revenue sur le devant de la scène, de façon plus indirecte donnant des informations très diverses et sur les différentes étapes de la collision.
Les Xi ont révélé tout d'abord que le système créé à l'énergie nominale du RHIC serait en équilibre thermique et chimique et que les températures de freeze-out chimique sont proches de la température de déconfinement prédite par QCD. Nous avons également étudié les phénomènes dynamiques collectifs, appelés flot, qui naissent des interactions entre constituants et se traduisent par une émission de matière dans des directions privilégiées de l'espace de phase. En accord avec leurs faibles sections efficaces d'interaction, les Xi semblent émis bien plus tôt que les particules plus légères. Toutefois, le fait que ces baryons subissent un flot important, laisse supposer qu'elles auraient développé un flot, donc qu'elles auraient été soumises à des interactions, avant la phase d'hadronisation, autrement dit, dans une phase partonique. Les partons subiraient donc des interactions résiduelles, contrairement à ce que préconisaient les théoriciens du milieu des années soixante-dix.
Par ailleurs, en 2003, les quatre expériences du RHIC ont révélé conjointement la mise en évidence du phénomène de jet-quenching dans les collisions d'ions lourds : il traduit une diminution de la production de particules chargées de très haute impulsion transverse s'expliquant par la perte d'énergie des partons dans un milieu très dense. Nous avons réalisé cette analyse en considérant les X et montré que non seulement ces baryons subissent un jet-quenching mais aussi qu'ils ont un comportement différent de celui des mésons. Une dépendance des phénomènes dynamiques au type de particules a ainsi été mise en évidence en accord avec les modèles de coalescence préconisant que les hadrons se forment à partir de la recombinaison des quarks. Là aussi, émergence des partons comme degrés de liberté pertinents.
A partir de ces résultats entre autres, certains théoriciens affirment la découverte du QGP à RHIC mais les expérimentateurs sont plus prudents et désirent auparavant confirmer et enrichir leurs résultats par l'étude d'autres observables qui viendraient corroborer ces observations. Ces années ont été particulièrement stimulantes par l'évolution de nos connaissances grâce aux formidables résultats produits par les quatre expériences du RHIC. Les « vielles » signatures ont fait peau neuve se transformant en sondes nouvelles et riches en informations originales. La conception du QGP a évolué : il ne s'agit plus d'un gaz parfait constitué de partons évoluant librement mais d'un sQGP.

Gli stili APA, Harvard, Vancouver, ISO e altri

Più fonti

Libri sul tema "Gluons"

Creutz, Michael. Quarks, gluons, and lattices. Cambridge [Cambridgeshire]: Cambridge University Press, 1986.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

International, Workshop on Physics with GeV Electrons and Gamma-Rays (2001 Sendai Japan). Physics with GeV electrons and gamma-rays: Proceedings of the International Workshop on Physics with GeV Electrons and Gamma-Rays, Sendai, Japan, February 13-15, 2001. Tokyo: Unviersal Academy Press, 2001.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Quarks and gluons: A century of particle charges. Singapore: World Scientific, 1999.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Rencontre de Moriond (22nd 1987 Les Arcs, Savoie, France.). Hadrons, quarks, and gluons: Proceedings of the Hadronic Session of the Twenty-second Rencontre de Moriond, Les Arcs-Savoie-France, March 15-21, 1987. Gif-sur-Yvette: Editions Frontières, 1987.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

D, Viollier R., Warner Nancy e University of Cape Town. Institute of Theoretical Physics and Astrophysics., a cura di. Quarks, gluons, and hadronic matter: Proceedings of the 1987 Cape Town Workshop. Singapore: World Scientific, 1987.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Laboratory), Topical Conference on Nuclear Chromodynamics (1988 Argonne National. Topical Conference on Nuclear Chromodynamics, Argonne National Laboratory, May 19-21, 1988. Singapore: World Scientific, 1988.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

M, Zinovʹev G., Shelest V. P e Instytut teoretychnoï fizyky (Akademii͡a︡ nauk Ukraïnsʹkoï RSR), a cura di. Adronnai͡a︡ materii͡a︡ v ėkstremalʹnykh uslovii͡a︡kh. Kiev: Nauk. dumka, 1986.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Antonino, Zichichi, a cura di. From quarks to black holes: Progress in understanding the logic of nature : proceedings of the International School of Subnuclear Physics. Singapore: World Scientific, 2005.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

International, School of Subnuclear Physics (44th 2006 Erice Italy). The logic of nature, complexity and new physics: From quark-gluon plasma to superstrings, quantum gravity and beyond : proceedings of the International School of Subnuclear Physics. Singapore: World Scientific, 2008.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Antonino, Zichichi, a cura di. The logic of nature, complexity and new physics: From quark-gluon plasma to superstrings, quantum gravity and beyond : proceedings of the International School of Subnuclear Physics. Singapore: World Scientific, 2008.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Più fonti

Capitoli di libri sul tema "Gluons"

Silva, P. J., O. Oliveira, D. Dudal, P. Bicudo e N. Cardoso. "Gluons at Finite Temperature". In Light Cone 2016, 95–101. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-65732-5_14.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Fritzsch, Harald. "Advantages of Color Octet Gluons". In Murray Gell-Mann and the Physics of Quarks, 131–35. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-92195-2_10.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Stock, Reinhard. "Relativistic Nucleus-Nucleus Collisions and the QCD Matter Phase Diagram". In Particle Physics Reference Library, 311–453. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-38207-0_7.

Testo completo

Abstract (sommario):

AbstractThis review will be concerned with our knowledge of extended matter under the governance of strong interaction, in short: QCD matter. Strictly speaking, the hadrons are representing the first layer of extended QCD architecture. In fact we encounter the characteristic phenomena of confinement as distances grow to the scale of 1 fm (i.e. hadron size): loss of the chiral symmetry property of the elementary QCD Lagrangian via non-perturbative generation of “massive” quark and gluon condensates, that replace the bare QCD vacuum. However, given such first experiences of transition from short range perturbative QCD phenomena (jet physics etc.), toward extended, non perturbative QCD hadron structure, we shall proceed here to systems with dimensions far exceeding the force range: matter in the interior of heavy nuclei, or in neutron stars, and primordial matter in the cosmological era from electro-weak decoupling (10−12 s) to hadron formation (0.5 ⋅ 10−5 s). This primordial matter, prior to hadronization, should be deconfined in its QCD sector, forming a plasma (i.e. color conducting) state of quarks and gluons: the Quark Gluon Plasma (QGP).

Gli stili APA, Harvard, Vancouver, ISO e altri

Povh, Bogdan, Klaus Rith, Christoph Scholz e Frank Zetsche. "Quarks, Gluons, and the Strong Interaction". In Particles and Nuclei, 97–111. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-662-05432-1_8.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Povh, Bogdan, Klaus Rith, Christoph Scholz, Frank Zetsche e Werner Rodejohann. "Quarks, Gluons, and the Strong Interaction". In Graduate Texts in Physics, 103–22. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-46321-5_8.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Satz, Helmut. "The Thermodynamics of Quarks and Gluons". In The Physics of the Quark-Gluon Plasma, 1–21. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-02286-9_1.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Economou, Eleftherios N. "From Quarks and Gluons to Hadrons". In From Quarks to the Universe, 123–31. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-20654-7_8.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Povh, Bogdan, Klaus Rith, Christoph Scholz e Frank Zetsche. "Quarks, Gluons, and the Strong Interaction". In Particles and Nuclei, 97–111. Berlin, Heidelberg: Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/978-3-642-87776-6_8.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Bialas, A., e W. Czyz. "Quarks and gluons in color fields". In Quark Matter, 173–76. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-83524-7_25.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Greensite, Jeff. "Ghosts, Gluons, and Dyson-Schwinger Equations". In An Introduction to the Confinement Problem, 179–91. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51563-8_11.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Atti di convegni sul tema "Gluons"

Karl, Gabriel. "Gluons in hadron spectroscopy". In AIP Conference Proceedings Volume 132. AIP, 1985. http://dx.doi.org/10.1063/1.35393.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Sridhar, K. "KK Gluons at NLO". In 10th International Symposium on Radiative Corrections (Applications of Quantum Field Theory to Phenomenology). Trieste, Italy: Sissa Medialab, 2013. http://dx.doi.org/10.22323/1.145.0044.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Larin, Sergey. "QCD with massive gluons". In XXII International Baldin Seminar on High Energy Physics Problems. Trieste, Italy: Sissa Medialab, 2015. http://dx.doi.org/10.22323/1.225.0018.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Larin, S. A. "Quantum chromodynamics with massive gluons". In XITH CONFERENCE ON QUARK CONFINEMENT AND HADRON SPECTRUM. AIP Publishing LLC, 2016. http://dx.doi.org/10.1063/1.4938688.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Suganuma, Hideo. "Lattice QCD Analysis for Gluons". In International Workshop on QCD Green’s Functions, Confinement and Phenomenology. Trieste, Italy: Sissa Medialab, 2010. http://dx.doi.org/10.22323/1.087.0044.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Chaichian, Masud. "Colour confinement and massive gluons". In Quarks, Strings and the Cosmos - Héctor Rubinstein Memorial Symposium. Trieste, Italy: Sissa Medialab, 2011. http://dx.doi.org/10.22323/1.109.0044.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Mukherjee, Asmita, Sreeraj Nair e Jai More. "Wigner Distributions of Quarks and Gluons". In XXV International Workshop on Deep-Inelastic Scattering and Related Subjects. Trieste, Italy: Sissa Medialab, 2017. http://dx.doi.org/10.22323/1.297.0224.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Ralston, John P. "How gluons spin in the proton". In The 11th International symposium on high energy spin physics. AIP, 1995. http://dx.doi.org/10.1063/1.48960.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Braghin, Fábio L., Ednaldo Barros Jr. e Ademar Paulo Jr. "Gluons and the NJL coupling constant". In XXXVI BRAZILIAN WORKSHOP ON NUCLEAR PHYSICS. AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4901796.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Natale, A. A. "Chiral symmetry, massive gluons and confinement". In XII HADRON PHYSICS. AIP, 2013. http://dx.doi.org/10.1063/1.4795955.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Rapporti di organizzazioni sul tema "Gluons"

Weinstein, Marvin. Quarks, Gluons and Frustrated Antiferromagnets. Office of Scientific and Technical Information (OSTI), ottobre 1999. http://dx.doi.org/10.2172/15073.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Boer, D., R. Venugopalan, M. Diehl, R. Milner, W. Vogelsang e et al. Gluons and the quark sea at high energies: distributions, polarization, tomography. Office of Scientific and Technical Information (OSTI), settembre 2011. http://dx.doi.org/10.2172/1034033.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Mueller, Alfred. Soft Gluons in the Finite Momentum Wave Function and the BFKL Pomeron. Office of Scientific and Technical Information (OSTI), luglio 2003. http://dx.doi.org/10.2172/813300.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Manly, Steven. Study the Collective Behavior of Quarks and Gluons in High Energy Nuclear Collisions. Final Report. Office of Scientific and Technical Information (OSTI), settembre 2008. http://dx.doi.org/10.2172/936784.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Keyvan, Farhad. A Search for Supersymmetric Quarks and Gluons in $p\bar{p}$ Collisions at 1.8-TeV with the CDF Detector. Office of Scientific and Technical Information (OSTI), gennaio 1996. http://dx.doi.org/10.2172/1422807.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Rosenberg, L. J. Study of hadronization using energy flow from e/sup +/e/sup -/ annihilation into quarks and gluons at. sqrt. s of 29 GeV. Office of Scientific and Technical Information (OSTI), novembre 1985. http://dx.doi.org/10.2172/6290682.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Manly, Steven L. Study of the Collective Characteristics of Quarks and Gluons in High Energy Nuclear Collisions. Final technical report. February 15, 1998 - December 31, 1998. Office of Scientific and Technical Information (OSTI), maggio 1999. http://dx.doi.org/10.2172/756726.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Rosenberg, Leslie J. The Study of Hadronization Using Energy Flow from e⁺e^- Annihilation into Quarks and Gluons at √s of 29 GeV. Office of Scientific and Technical Information (OSTI), giugno 2018. http://dx.doi.org/10.2172/1454009.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Bern, Z. Two-Loop Gluon to Gluon-Gluon Splitting Amplitudes in QCD. Office of Scientific and Technical Information (OSTI), aprile 2004. http://dx.doi.org/10.2172/826914.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Schwartz, Bertha, Vaclav Vetvicka, Ofer Danai e Yitzhak Hadar. Increasing the value of mushrooms as functional foods: induction of alpha and beta glucan content via novel cultivation methods. United States Department of Agriculture, gennaio 2015. http://dx.doi.org/10.32747/2015.7600033.bard.

Testo completo

Abstract (sommario):

During the granting period, we performed the following projects: Firstly, we differentially measured glucan content in several pleurotus mushroom strains. Mushroom polysaccharides are edible polymers that have numerous reported biological functions; the most common effects are attributed to β-glucans. In recent years, it became apparent that the less abundant α-glucans also possess potent effects in various health conditions. In our first study, we explored several Pleurotus species for their total, β and α-glucan content. Pleurotuseryngii was found to have the highest total glucan concentrations and the highest α-glucans proportion. We also found that the stalks (stipe) of the fruit body contained higher glucan content then the caps (pileus). Since mushrooms respond markedly to changes in environmental and growth conditions, we developed cultivation methods aiming to increase the levels of α and β-glucans. Using olive mill solid waste (OMSW) from three-phase olive mills in the cultivation substrate. We were able to enrich the levels mainly of α-glucans. Maximal total glucan concentrations were enhanced up to twice when the growth substrate contained 80% of OMSW compared to no OMSW. Taking together this study demonstrate that Pleurotuseryngii can serve as a potential rich source of glucans for nutritional and medicinal applications and that glucan content in mushroom fruiting bodies can be further enriched by applying OMSW into the cultivation substrate. We then compared the immune-modulating activity of glucans extracted from P. ostreatus and P. eryngii on phagocytosis of peripheral blood neutrophils, and superoxide release from HL-60 cells. The results suggest that the anti-inflammatory properties of these glucans are partially mediated through modulation of neutrophileffector functions (P. eryngiiwas more effective). Additionally, both glucans dose-dependently competed for the anti-Dectin-1 and anti-CR3 antibody binding. We then tested the putative anti-inflammatory effects of the extracted glucans in inflammatory bowel disease (IBD) using the dextran sulfate sodium (DSS)–induced model in mice. The clinical symptoms of IBD were efficiently relieved by the treatment with two different doses of the glucan from both fungi. Glucan fractions, from either P. ostreatus or P. eryngii, markedly prevented TNF-α mediated inflammation in the DSS–induced inflamed intestine. These results suggest that there are variations in glucan preparations from different fungi in their anti-inflammatory ability. In our next study, we tested the effect of glucans on lipopolysaccharide (LPS)-induced production of TNF-α. We demonstrated that glucan extracts are more effective than mill mushroom preparations. Additionally, the effectiveness of stalk-derived glucans were slightly more pronounced than of caps. Cap and stalk glucans from mill or isolated glucan competed dose-dependently with anti-Dectin-and anti-CR-3 antibodies, indicating that they contain β-glucans recognized by these receptors. Using the dextran sulfate sodium (DSS)-inflammatory bowel disease mice model, intestinal inflammatory response to the mill preparations was measured and compared to extracted glucan fractions from caps and stalks. We found that mill and glucan extracts were very effective in downregulatingIFN-γ and MIP-2 levels and that stalk-derived preparations were more effective than from caps. The tested glucans were equally effective in regulating the number of CD14/CD16 monocytes and upregulating the levels of fecal-released IgA to almost normal levels. In conclusion, the most effective glucans in ameliorating some IBD-inflammatory associated symptoms induced by DSS treatment in mice were glucan extracts prepared from the stalk of P. eryngii. These spatial distinctions may be helpful in selecting more effective specific anti-inflammatory mushrooms-derived glucans. We additionally tested the effect of glucans on lipopolysaccharide-induced production of TNF-α, which demonstrated stalk-derived glucans were more effective than of caps-derived glucans. Isolated glucans competed with anti-Dectin-1 and anti-CR3 antibodies, indicating that they contain β-glucans recognized by these receptors. In conclusion, the most effective glucans in ameliorating IBD-associated symptoms induced by DSS treatment in mice were glucan extracts prepared from the stalk of P. eryngii grown at higher concentrations of OMSW. We conclude that these stress-induced growing conditions may be helpful in selecting more effective glucans derived from edible mushrooms. Based on the findings that we could enhance glucan content in Pleurotuseryngii following cultivation of the mushrooms on a substrate containing different concentrations of olive mill solid waste (OMSW) and that these changes are directly related to the content of OMSW in the growing substrate we tested the extracted glucans in several models. Using dextran sulfate sodium (DSS)–inflammatory bowel disease (IBD) mice model, we measured the colonic inflammatory response to the different glucan preparations. We found that the histology damaging score (HDS) resulting from DSS treatment reach a value of 11.8 ± 2.3 were efficiently downregulated by treatment with the fungal extracted glucans, glucans extracted from stalks cultivated at 20% OMSWdownregulated to a HDS value of 6.4 ± 0.5 and at 80% OMSW showed the strongest effects (5.5 ± 0.6). Similar downregulatory effects were obtained for expression of various intestinal cytokines. All tested glucans were equally effective in regulating the number of CD14/CD16 monocytes from 18.2 ± 2.7 % for DSS to 6.4 ± 2.0 for DSS +glucans extracted from stalks cultivated at 50% OMSW. We finally tested glucans extracted from Pleurotuseryngii grown on a substrate containing increasing concentrations of olive mill solid waste (OMSW) contain greater glucan concentrations as a function of OMSW content. Treatment of rat Intestinal epithelial cells (IEC-6) transiently transfected with Nf-κB fused to luciferase demonstrated that glucans extracted from P. eryngii stalks grown on 80% OMSWdownregulatedTNF-α activation. Glucans from mushrooms grown on 80% OMSW exerted the most significant reducing activity of nitric oxide production in lipopolysaccharide (LPS) treated J774A.1 murine macrophages. The isolated glucans were tested in vivo using the Dextran Sodium Sulfate (DSS) induced colitis in C57Bl/6 mice and found to reduce the histology damaging score resulting from DSS treatment. Expression of various intestinal cytokines were efficiently downregulated by treatment with the fungal extracted glucans. We conclude that the stress-induced growing conditions exerted by OMSW induces production of more effective anti-inflammatory glucans in P. eryngii stalks.

Gli stili APA, Harvard, Vancouver, ISO e altri

Offriamo sconti su tutti i piani premium per gli autori le cui opere sono incluse in raccolte letterarie tematiche. Contattaci per ottenere un codice promozionale unico!