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One of the main goals of future electron-ion colliders is to improve our understanding of the structure of hadrons. In this letter, we study the exclusive ηc production by γ⁎γ interactions in eA collisions and demonstrate that future experimental analysis of this process can be used to improve the description of the ηc transition form factor. The rapidity, transverse momentum and photon virtuality distributions are estimated considering the energy and target configurations expected to be present at the EIC, EicC and LHeC and assuming different predictions for the light-front wave function of the ηc meson. Our results indicate that the electron-ion colliders can be considered an alternative to providing supplementary data to those obtained in e−e+ colliders.

In this paper we investigate the impact of the higher - twist effects, resummed by the non - linear approaches for the QCD dynamics, on the inclusive observables that will be measured in future electron - ion colliders. We assume a phenomenological model for the dipole - nucleus scattering amplitude which takes into account the non - linear corrections and estimate the contribution of the different twists for $F_2^A(x,Q^2)$, $F_L^A(x,Q^2)$ and $\partial F_2^A /\partial ln Q^2$ considering different values of the Bjorken - $x$ variable, photon virtuality $Q^2$ and atomic number $A$. A comparison with the full predictions is performed and the impact of the distinct twists is estimated. Our results indicate that a future analysis of the logarithmic $Q^2$ slope and longitudinal structure function will allow us to probe the presence of the non - linear effects on the QCD dynamics., Comment: 9 pages, 6 figures. Improved version published in EPJA

One of the main goals of future electron-ion colliders is to improve our understanding of the structure of hadrons. In this letter, we study the exclusive $η_c$ production by $γ^{*} γ$ interactions in $eA$ collisions and demonstrate that future experimental analysis of this process can be used to improve the description of the $η_c$ transition form factor. The rapidity, transverse momentum and photon virtuality distributions are estimated considering the energy and target configurations expected to be present at the EIC, EicC and LHeC and assuming different predictions for the light-front wave function of the $η_c$ meson. Our results indicate that the electron-ion colliders can be considered an alternative to providing supplementary data to those obtained in $e^- e^+$ colliders., 11 pages, 5 figures

Orofacial injuries are extremely common in contact sports and the culture of competitiveness provides an environment where injuries are frequent, especially impacts on dental elements, known as dental trauma. This work aims to make a systematic review of the scientific literature on the effectiveness of mouthguards in reducing orofacial injuries during sports activities. After screening the databases and removing duplicates, 46 studies were identified. After selecting the title and carefully reading the abstracts, articles that did not meet the inclusion and exclusion criteria were excluded, and the systematic review was performed with 13 articles. The findings of the present systematic review with studies carried out by FEM evaluating the biomechanical behavior of tensions, stress distribution and deformations indicate that the use of BP reduces the risk of orofacial injuries during sports activities and that a thickness of 3mm or 4mm seems to be most suitable. Las lesiones orofaciales son extremadamente comunes en los deportes de contacto y la cultura de la competitividad proporciona un ambiente donde las lesiones son frecuentes, especialmente los impactos en los elementos dentales, conocidos como trauma dental. Este trabajo tiene como objetivo realizar una revisión sistemática de la literatura científica sobre la efectividad de los protectores bucales en la reducción de lesiones orofaciales durante la práctica deportiva. Después de examinar las bases de datos y eliminar los duplicados, se identificaron 46 estudios. Después de seleccionar el título y leer atentamente los resúmenes, se excluyeron los artículos que no cumplían con los criterios de inclusión y exclusión, y se realizó la revisión sistemática con 13 artículos. Los hallazgos de la presente revisión sistemática con estudios realizados por FEM que evalúan el comportamiento biomecánico de tensiones, distribución de esfuerzos y deformaciones indican que el uso de BP reduce el riesgo de lesiones orofaciales durante la actividad deportiva y que un espesor de 3 mm o 4 mm parece ser más adecuado As injurias orofaciais são extremamente comuns em esportes de contato e a cultura da competitividade fornece um ambiente onde as lesões são frequentes, principalmente os impactos em elementos dentários, conhecidos como traumatismo dentário. Esse trabalho tem por objetivo fazer uma revisão sistemática da literatura científica sobre a eficácia dos protetores bucais na redução das lesões orofaciais durante atividades esportivas. Após a triagem dos bancos de dados e remoção de duplicatas, 46 estudos foram identificados. Após a seleção do título e leitura cuidadosa dos resumos foram realizadas exclusões dos artigos que não seguiam critérios de inclusão e exclusão, e a revisão sistemática foi realizada com 13 artigos. Os achados da presente revisão sistemática com estudos realizados por MEF avaliando o comportamento biomecânico de tensões, distribuição de estresse e as deformações indicam que o uso do PB reduz os riscos de lesões orofaciais durante as atividades esportivas e que a espessura de 3mm ou 4mm parecem ser mais adequadas.

The aesthetic standard requires beautiful and harmonious smiles, which encourages the search for dental procedures to correct imperfections in the stomatognathic system. In periodontics, plastic surgeries with the aim of correcting the so-called gummy smile are becoming progressively routine. With the advent of new technologies, aesthetic treatment options increase, becoming less invasive, less traumatic and with greater predictability, enabling emphasis in this area. In this sense, the perioguide is taken as an object of research, since its purpose is to help dentists in predicting gummy smile correction surgery. This work is a single case study, as it intends to report a work dealing with gingivoplasty/gingivectomy surgery using the perioguide. The interdisciplinary work between the specialties of Periodontics was concluded, with Radiology aided by technology, which enables the improvement and optimization of gingivoplasty/gingivectomy surgery. The use of the perioguide was a differential for treatment success. El estándar estético requiere sonrisas hermosas y armoniosas, lo que incentiva la búsqueda de procedimientos dentales para corregir imperfecciones en el sistema estomatognático. En periodoncia, las cirugías plásticas con el objetivo de corregir la llamada sonrisa gingival son cada vez más rutinarias. Con el advenimiento de las nuevas tecnologías, aumentan las opciones de tratamiento estético que se han vuelto cada vez menos invasivas, menos traumáticas y con mayor previsibilidad, lo que permite hacer hincapié en esta área. En este sentido, la perioguía se toma como objeto de investigación, ya que su finalidad es ayudar a los odontólogos en la predicción de la cirugía de corrección de la sonrisa gingival. Este trabajo es un estudio de caso único, ya que pretende informar de un trabajo sobre la cirugía de gingivoplastia / gingivectomía utilizando la perioguía. Se concluyó el trabajo interdisciplinario entre las especialidades de Periodoncia, con Radiología asistida por tecnología, que permite la mejora y optimización de la cirugía de gingivoplastia / gingivectomía. El uso de la perioguía fue un diferencial para el éxito del tratamento. O padrão estético exige sorrisos bonitos e harmoniosos, o que incentiva a procura por procedimentos odontológicos para correção de imperfeições no sistema estomatognático. Na periodontia as cirurgias plásticas com intuito de corrigir o chamado sorriso gengival vêm sendo cada vez mais rotineiras. Com o advento de novas tecnologias, aumentam as opções de tratamento estético que se tornaram cada vez menos invasivos, menos traumáticos e com maior previsibilidade, possibilitando ênfase neste âmbito. Nesse sentido, toma-se o perioguide como objeto de pesquisa, uma vez que o que o mesmo se propõe a auxiliar o cirurgião-dentista na previsibilidade na cirurgia de correção do sorriso gengival. Este trabalho trata-se de um estudo de caso único, pois possui a intenção de relatar um trabalho que trata cirurgia de gengivoplastia/gengivectomia com utilização do perioguide. Concluiu-se que a atuação interdisciplinar entre as especialidades da Periodontia com a Radiologia auxiliada com a tecnologia possibilita aperfeiçoar e otimizar a cirurgia de gengivoplastia/gengivectomia. O uso do perioguide foi um diferencial para sucesso do tratamento.

We investigate the production of the fully - heavy tetraquark states $T_{4Q}$ in the $����$ interactions present in proton-proton, proton-nucleus and nucleus-nucleus collisions at the CERN Large Hadron Collider (LHC). We focus on the $����\rightarrow {\cal{Q}}{\cal{Q}}$ (${\cal{Q}} = J/��,\, ��$) subprocess, mediated by the $T_{4Q}$ resonance in the $s$ - channel, and present predictions for the hadronic cross sections considering the kinematical ranges probed by the ALICE and LHCb Collaborations. Our results demonstrate that the experimental study of this process is feasible and can be used to investigate the existence and properties of the $T_{4c}(6900)$ and $T_{4b}(19000)$ states., 5 pages, 2 figures, 2 tables. arXiv admin note: substantial text overlap with arXiv:1809.08125

Ultra-peripheral collisions (UPCs) involving heavy ions and protons are the energy frontier for photon-mediated interactions. UPC photons can be used for many purposes, including probing low-$x$ gluons via photoproduction of dijets and vector mesons, probes of beyond-standard-model processes, such as those enabled by light-by-light scattering, and studies of two-photon production of the Higgs., Letter of Interest submitted to Snowmass 2021

A phenomenological study of the isolated photon production in high energy $pp$ and $pA$ collisions at RHIC and LHC energies is performed. Using the color dipole approach we investigate the production cross section differential in the transverse momentum of the photon considering three different phenomenological models for the universal dipole cross section. We also present the predictions for the rapidity dependence of the ratio of $pA$ to $pp$ cross sections. As a further test of the formalism, for different energies and photon rapidites we analyse the correlation function in azimuthal angle $\Delta\phi$ between the photon and a forward pion. The characteristic double-peak structure of the correlation function around $\Delta \phi\simeq \pi$ observed previously for Drell-Yan pair production is found for isolated photon emitted into the forward rapidity region which can be tested by future experiments., Comment: 11 pages, 9 figures. Improved version to be published in Physical Review D

We derive the light-front wave function (LFWF) representation of the γ*γ*→ηc(1S),ηc(2S) transition form factor F(Q12,Q22) for two virtual photons in the initial state. For the LFWF, we use different models obtained from the solution of the Schrödinger equation for a variety of cc¯ potentials. We compare our results to the BABAR experimental data for the ηc(1S) transition form factor, for one real and one virtual photon. We observe that the onset of the asymptotic behavior is strongly delayed and discuss applicability of the collinear and/or massless limit. We present some examples of two-dimensional distributions for F(Q12,Q22). A factorization breaking measure is proposed and factorization breaking effects are quantified and shown to be almost model independent. Factorization is shown to be strongly broken, and a scaling of the form factor as a function of Q¯2=(Q12+Q22)/2 is obtained.