Physics Beyond the Standard Model: Focusing on the Muon Anomaly

We present a model based on the implication of an exceptional E_{6}-GUT symmetry for the anomalous magnetic moment of the muon. We follow a particular chain of breakings with Higgses in the 78 and 351 representations. We analyse the radiative correction contributions to the muon mass and the effects of the breaking of the so-called Weinberg symmetry. We also estimate the range of values of the parameters of our model.Comment: 14 RevTeX pages, 5 figure

Upper bound for the conductivity of nanotube networks

Films composed of nanotube networks have their conductivities regulated by the junction resistances formed between tubes. Conductivity values are enhanced by lower junction resistances but should reach a maximum that is limited by the network morphology. By considering ideal ballistic-like contacts between nanotubes we use the Kubo formalism to calculate the upper bound for the conductivity of such films and show how it depends on the nanotube concentration as well as on their aspect ratio. Highest measured conductivities reported so far are approaching this limiting value, suggesting that further progress lies with nanowires other than nanotubes.Comment: 3 pages, 1 figure. Minor changes. Accepted for publication in Applied Physics Letter

The multidisciplinary role of cultural management: A look for communication as management tool and key-activity

The purpose of this article is to explore the communication as tool and key-activity, within the scope of multidisciplinary character of cultural management and cultural equipment’s multimensionality. It's a hybrid study - conceptual and empirical - and exploratory, based on literature review and illustrated with descriptive analysis from data collected by 573 questionnaires regarding a specific event. Was followed a mixed methodology – qualitative and quantitative - and an interpretative paradigm. Were pulled out 3 conclusions: 1) The first one is the awareness need by the cultural management for an adoption of multidisciplinary posture, lined up by the multidimensional nature of cultural equipment’s and the organizational environment, in a purpose to match public expectations; 2) The second one is the need of comprehend the communication as tool and key-activity to engender culture value in both organizational environments: inside and outside; 3) The third, due questionnaire application, resides in the mass-media advantage over digitals, for public fund. This article: a) provides inputs for an interterritorial plan creation; b) contribute for the discussion about ideologic construction of professional category, instrands of thought building about its functions and concerns; c) increase communication importance as key-activity; d) highlight the power of media in cultural events; e) contributes to sign the need for a multidisciplinary training for cultural managers. The article value resides in reinforce the discussion for a new vision about the action ray of the cultural manager, supported in the connection between the equipment’s dimensions and the multidisciplinary posture.info:eu-repo/semantics/publishedVersio

Cosmic String Wakes in Scalar-Tensor Gravities

The formation and evolution of cosmic string wakes in the framework of a scalar-tensor gravity are investigated in this work. We consider a simple model in which cold dark matter flows past an ordinary string and we treat this motion in the Zel'dovich approximation. We make a comaprison between our results and previous results obtained in the context of General Relativity. We propose a mechanism in which the contribution of the scalar field to the evolution of the wakes may lead to a cosmological observation.Comment: Replaced version to be published in the Classical and Quantum Gravit

Universal behavior at discontinuous quantum phase transitions

Discontinuous quantum phase transitions besides their general interest are clearly relevant to the study of heavy fermions and magnetic transition metal compounds. Recent results show that in many systems belonging to these classes of materials, the magnetic transition changes from second order to first order as they approach the quantum critical point (QCP). We investigate here some mechanisms that may be responsible for this change. Specifically the coupling of the order parameter to soft modes and the competition between different types of order near the QCP. For weak first order quantum phase transitions general results are obtained. In particular we describe the thermodynamic behavior at this transition when it is approached from finite temperatures. This is the discontinuous equivalent of the non-Fermi liquid trajectory close to a conventional QCP in a heavy fermion material.Comment: 7 pages, 3 figure

Enhanced compatibility between coconut fibers/PP via chemical modification for 3D printing

Aiming to produce high-quality bio-based 3D printed products, in this work, coconut fibers were chemical modified using caprolactone. Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic reasonance (NMR) confirmed the grafting of the hydroxyl groups present on the surface of the fibers with caprolactone units. Furthermore, from contact angle (CA) analyses, the higher hydrophobicity of fibers after chemical treatment was confirmed, which improved its affinity with PP. The enhanced filler/matrix compatibility was reflected on the mechanical performance and processability of the ensuing composites. The modified fibers derived composites showed higher stiffness and higher melting flow index (MFI), when compared to the untreated counterparts. The composites were used to produce 3D printed specimens. Smother filaments were obtained using modified fibers, which confirms the better compatibility of fibers/PP. The surface of the 3D printed composite specimen produced using treated fibers, presented smooth surface, similar to the PP. This observation highlights the enhancement of the 3D printing quality due to the chemical modification of fibers. © 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG.publishe