Entanglement Entropy of the Low-Lying Excited States and Critical Properties of an Exactly Solvable Two-Leg Spin Ladder with Three-Spin Interactions

In this work, we investigate an exactly solvable two-leg spin ladder with three-spin interactions. We obtain analytically the finite-size corrections of the low-lying energies and determine the central charge as well as the scaling dimensions. The model considered in this work has the same universality class of critical behavior of the XX chain with central charge c=1. By using the correlation matrix method, we also study the finite-size corrections of the Renyi entropy of the ground state and of the excited states. Our results are in agreement with the predictions of the conformal field theory.Comment: 10 pages, 6 figures, 2 table

Re-inventing Portuguese ceramic tiles: Using shape grammars as generative method and the impact on design methodology

The following paper describes the process and results achieved with the workshop entitled ‘Re-inventing Portuguese ceramic tiles’ reflecting on design methodology and design teaching. Workshop participants were invited to rethink ceramic tile patterns developing a different process which used shape grammars as a generative system. Each participant group developed a three stage task using shape grammars principles and methodology. At a first stage all were exposed to the shape grammar formulation and rule system. At a second stage they had to explore shape rules and create a novel shape grammar. Each design solutions generated were presented for discussion. On the last stage all groups were presented with pre-existing patterns, invited to infer a grammar by extracting shape rules observed through design patterns and then extrapolate these findings to a third dimension. The preliminary results of stages two and three are of particular relevance in shape grammar research: shape grammar formulae does not constitute an intuitive process to most creative designers which are often trained to design singular solutions for a specific problem, more than one operative shape grammar can be formulated to represent the same corpus of solutions and lastly the generative potential of grammars transcends the normal capacities of the original grammarist aiding in design exploration and enlarging the corpus of feasible solutions. This paper also reflects on the impact of shape grammars as a design methodology.info:eu-repo/semantics/acceptedVersio

Manejo reprodutivo de matrizes e reprodutores caprinos em sistema de produção de leite.

O presente documento destaca os aspectos relevantes e apresenta recomendações no âmbito do Sistema de Produção de Leite, destacando desde as condições adequadas para a implantação do manejo reprodutivo, eficiência reprodutiva, seleção de eprodutores e matrizes, até o manejo das crias.bitstream/CNPC/20259/1/doc65.pd

Comparison of modified Hackethal bundle nailing versus anterograde nailing for fixation of surgical neck fractures of the humerus: Retrospective study of 105 cases

AbstractIntroductionIntramedullary fixation of displaced surgical neck fractures of the humerus can be performed either by retrograde pinning or anterograde nailing. The goal of the current study was to compare the postoperative reduction and stability obtained with these two techniques.HypothesisIntramedullary nailing will provide the best reduction and stabilization of these fractures.Patients and methodsThis was a multicenter retrospective study that included patients with sub-tuberosity fractures with or without greater tuberosity fragment. These patients were treated either by retrograde Hackethal type pinning (group 1) or Telegraph anterograde nailing (group 2). To be included, patients needed to have A/P and lateral X-rays that had been taken before the surgery, immediately post-operative, between four and six weeks post-operative, and at the last follow-up. The outcomes were head angulation, translation and greater tuberosity position.ResultsOne hundred and five patients (40 retrograde pinning and 65 anterograde nailing) with an average age of 69 years (18–97 years) were included. The pre-operative fracture displacement was similar between the two groups. After the surgery, the A/P head angulation had been corrected in 72.5% of patients in group 1 and 84% in group 2 (no significant difference). Translation was still present in 17.5% of patients in group 1 and 1.5% in group 2 (P<0.05). At the last follow-up, union was achieved without residual angulation on lateral X-rays in 71% of patients in group 1 and 88% in group 2 (P<0.05). The fractures had healed with residual translation is 19.5% of patients in group 1 and 3% in group 2 (P<0.05).Discussion and conclusionIn cases of displaced surgical neck fractures with or without a greater tuberosity fragment, anterograde nailing provides better reduction and stability than retrograde pinning. However, fixation of the greater tuberosity fragment must be improved.Level of evidenceIV (retrospective comparative study)

"No-Scalar-Hair" Theorems for Nonminimally Coupled Fields with Quartic Self-Interaction

Self-gravitating scalar fields with nonminimal coupling to gravity and having a quartic self-interaction are considered in the domain of outer communications of a static black hole. It is shown that there is no value of the nonminimal coupling parameter $\zeta$ for which nontrivial static black hole solutions exist. This result establishes the correctness of Bekenstein ``no-scalar-hair'' conjecture for quartic self-interactions.Comment: 8 pages, RevTeX

Understanding the use of Virtual Reality in Marketing: a text mining-based review

The current study intends to highlight the most relevant studies in simulated realities with special attention to VR and marketing, showing how studies have evolved over time and discussing the findings. A text-mining approach using a Bayesian statistical topic model called latent Dirichlet allocation is employed to conduct a comprehensive analysis of 150 articles from 115 journals, all indexed in Web of Science. The findings reveal seven relevant topics, as well as the number of articles published over time, the authors most cited in VR papers and the leading journals in each topic. The article also provides theoretical and practical implications and suggestions for further research.info:eu-repo/semantics/acceptedVersio

Influence of Operational Parameters on Photocatalytic Degradation of Linuron in Aqueous TiO2 Pillared Montmorillonite Suspension

TiO2 pillared clay was prepared by intercalation of titan polyoxocation into interlamelar space of an Algerian montmorillonite and used for the photocatalytic degradation of the linuron herbicide as a target pollutant in aqueous solution. The TiO2 pillared montmorillonite (Mont-TiO2) was characterized by X-ray photoelectron spectroscopy (XPS), X-Ray diffraction (XRD), X-Ray fluorescence (XRF), scanning electronic microscopy (SEM), thermogravimetry and differential thermal analysis (TG-DTA), Fourier transformed infra-red (FT-IR), specific area and porosity determinations. This physicochemical characterization pointed to successful TiO2 pillaring of the clay. The prepared material has porous structure and exhibit a good thermal stability as indicated by its surface area after calcination by microwave. The effects of operating parameters such as catalyst loading, initial pH of the solution and the pollutant concentration on the photocatalytic efficiency and COD removal  were evaluated. Under initial pH of the solution around seven, pollutant concentration of 10 mg/L and 2.5 g/L of catalyst at room temperature, the degradation efficiency and COD removal of linuron was best then the other operating conditions. It was observed that operational parameters play a major role in the photocatalytic degradation process. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).