Golden tilings

A. Pinto and D. Sullivan [3] proved a one-to-one correspondence between: (i) Cl+ conjugacy classes of expanding circle maps; (ii) solenoid functions and (iii) Pinto-Sullivan's dyadic tilings on the real line. Here, we prove a one-to-one correspondence between: (i) golden tilings; (ii) smooth conjugacy classes of golden diffeomorphism of the circle that are fixed points of renormalization; (iii) smooth conjugacy classes of Anosov difeomorphisms, with an invariant measure absolutely continuous with respect to the Lebesgue measure, that are topologically conjugated to the Anosov automorphism G(x, y) = (x + y, x) and (iv) solenoid functions

Evaluation of the Stiffness Effect of Pipe Supports in Relation to Static and Dynamic Loads in a Flexibility Analysis

Piping flexibility analysis is done to ensure structural integrity in all operating conditions that may occur over the life of a system, whether static or dynamic. In industrial designs generally the rigidity of the support is neglected in the analysis of flexibility. The work presents an evaluation of the loads transmitted the structures in function of the rigidity of the pipe support. The evaluation was done through computer simulation using finite element techniques. The computational simulation made possible the evaluation of the forces transmitted to the support structures of an existing project of an orifice station, when considering the rigidity of the support. The work also shows that it is possible to refine projects when taken into consideration the influence of the rigidity of the supports, making a more adequate sizing the structure, portraying more faithfully the behavior of the system. The work also evaluates the influence, advantages and disadvantages in the use of stiffness in the supports with regard to the load transmitted to the support structures (support, base and tube)

Ladrilhamentos dourados da recta real

Apresentaremos a definição de sucessão dourada {r_i}. Estas sucessões possuem a propriedade de serem Fibonacci quasi-periodicas e determinam um ladrilhamento na recta real. Provaremos uma correspondência bijectiva entre: (i) sucessões douradas; (ii) Classes de conjugação diferenciáveis de difeomorfismos de Anosov na classe de conjugação topológica do automorfismo hiperbólico do toro G(x,y) =(x+y,x); (iii) Classes de conjugação diferenciáveis de difeomorfismos da circunferência com número de rotação igual ao inverso do número de ouro e que são pontos fixos do operador renormalização

Inositol phosphate kinases in the eukaryote landscape

Inositol phosphate encompasses a large multifaceted family of signalling molecules that originate from the combinatorial attachment of phosphate groups to the inositol ring. To date, four distinct inositol kinases have been identified, namely, IPK, ITPK, IPPK (IP5-2K), and PPIP5K. Although, ITPKs have recently been identified in archaea, eukaryotes have taken advantage of these enzymes to create a sophisticated signalling network based on inositol phosphates. However, it remains largely elusive what fundamental biochemical principles control the signalling cascade. Here, we present an evolutionary approach to understand the development of the 'inositol phosphate code' in eukaryotes. Distribution analyses of these four inositol kinase groups throughout the eukaryotic landscape reveal the loss of either ITPK, or of PPIP5K proteins in several species. Surprisingly, the loss of IPPK, an enzyme thought to catalyse the rate limiting step of IP6 (phytic acid) synthesis, was also recorded. Furthermore, this study highlights a noteworthy difference between animal (metazoan) and plant (archaeplastida) lineages. While metazoan appears to have a substantial amplification of IPK enzymes, archaeplastida genomes show a considerable increase in ITPK members. Differential evolution of IPK and ITPK between plant and animal lineage is likely reflective of converging functional adaptation of these two types of inositol kinases. Since, the IPK family comprises three sub-types IPMK, IP6K, and IP3-3K each with dedicated enzymatic specificity in metazoan, we propose that the amplified ITPK group in plant could be classified in sub-types with distinct enzymology

Stress Analysis on a “L” shape Truss Optimization

The metal construction market in Brazil has grown significantly over the past few years. The weight reductions and performance increase of mechanical pieces obtained by using optimization techniques are significant to the point that currently its use is critical to define that competitiveness of the metal-mechanical engineering industries, and its undeniable importance in reducing costs. The optimization applied in the mechanical part design consists of using computational methods for dimensions, shape or optimal topology of parts. This study aims to propose a study methodology to analyse the stress distribution thought the use of mathematical software and photoelasticity techniques, to propose a new structural profile, lighter and more efficient, which may be used as solution to overcome the current constructive limitations

Hidden musculoskeletal involvement in inflammatory bowel disease: a multicenter ultrasound study

BACKGROUND: Inflammatory bowel diseases are associated with a variety of extra-intestinal manifestations. The most frequent of these is joint involvement, which affects 16-33 % of IBD patients. Our aim was to evaluate the ultrasound prevalence of sub-clinical joint and entheseal involvement in patients with IBD without musculoskeletal symptoms, and to correlate the US findings with clinical and laboratory variables. METHODS: We recorded the clinical and laboratory data of 76 patients with IBD, 20 patients with spondyloarthritis (SpA) and 45 healthy controls at three rheumatology centers. All of the IBD patients and healthy controls were clinically examined by a rheumatologist in order to confirm the absence of musculoskeletal symptoms, and all of the subjects underwent grey-scale (GS) and power Doppler (PD) US examinations of the second and third metacarpophalangeal joints, knees and lower limbs in order to detect joint or entheseal abnormalities. RESULTS: A total of 1410 entheseal sites and 1410 joints were evaluated by US. Of the 76 patients with IBD, 64 (84.1 %) had at least one GS entheseal abnormality, and 11 (13.9 %) had more than one PD-positive entheseal site; 32 (42.1 %) showed sub-clinical joint involvement. There was a significant difference between the IBD patients and healthy controls in terms of global entheseal, PD-positive entheseal, and joint involvement (p < 0.0001), but no difference between the IBD and SpA patients. Anti-neutrophil cytoplasmic antibodies predicted entheseal involvement in patients with IBD (OR 6.031; p = 0.015). CONCLUSIONS: The prevalence of sub-clinical joint and entheseal involvement was higher in IBD patients than healthy controls, but there was no difference between the IBD and SpA patients

Connectivity of the Pulley Ridge with remote locations as inferred from satellite- tracked drifter trajectories

Using historical (1994-2017) satellite‐tracked surface drifter trajectory data, we conduct a probabilistic Lagrangian circulation study which sheds light on the connectivity of Pulley Ridge with other locations in the Gulf of Mexico and adjacent areas. The analysis reveals that Pulley Ridge is connected with the North Atlantic, the Caribbean Sea, and most of the Gulf of Mexico. Preferred connecting pathways are identified and arrival times to potential reef sites computed. The study demonstrates the importance of Pulley Ridge as a source for neighboring regions like the Dry Tortugasa, the Florida Keys, Campeche Bank, and the east Florida coast as well as a self‐recruitment area for species with short competence time. The study further suggests that the reefs in the Caribbean Sea, the Dry Tortugas, the western Florida Keys, and the West Florida Shelf can act as sources for Pulley Ridge, indicating the importance of Pulley Ridge as a central refugium for species in the Gulf of Mexico

A new displacement-based approach to calculate stress intensity factors with the boundary element method

The analysis of cracked brittle mechanical components considering linear elastic fracture mechanics is usually reduced to the evaluation of stress intensity factors (SIFs). The SIF calculation can be carried out experimentally, theoretically or numerically. Each methodology has its own advantages but the use of numerical methods has be-come very popular. Several schemes for numerical SIF calculations have been developed, the J-integral method being one of the most widely used because of its energy-like formulation. Additionally, some variations of the J-integral method, such as displacement-based methods, are also becoming popular due to their simplicity. In this work, a simple displacement-based scheme is proposed to calculate SIFs, and its performance is compared with contour integrals. These schemes are all implemented with the Boundary Element Method (BEM) in order to exploit its advantages in crack growth modelling. Some simple examples are solved with the BEM and the calculated SIF values are compared against available solutions, showing good agreement between the different schemes

CARD15 mutations and colorectal cancer in a South European country

PURPOSE: CARD15 mutations are associated with higher susceptibility to Crohn's disease (CD) and longstanding colonic CD increases the risk of developing colorectal cancer (CRC). The relation between these mutations and sporadic CRC remains controversial. The aim of this study was to assess whether germline and/or somatic CARD15 mutations are risk factors for sporadic CRC in Portugal and whether there are genotype-phenotype correlations in these patients. METHODS: The three main CARD15 mutations (R702W, G908R and 3020insC) were researched in 112 sporadic CRC patients and 152 healthy subjects. RESULTS: Overall, CARD15 mutations were found in 18 patients (16.1%) and in 15 controls (9.9%; p = 0.132). Individually, the incidence of R702W was significantly higher in patients than in controls (12.5% vs. 5.3%, p = 0.035), whereas the genotype frequencies for G908R (2.7% vs. 3.3%) and 3020insC (0.9% vs. 1.3%) were not statistically different between the two groups. Entire genotypic agreement was found in patients genotyped for blood and neoplastic DNA. A significantly higher incidence of CARD15 mutations was detected in patients with CRC diagnosed under 60 years old (28.6% vs. 10.4%, p = 0.015) and in female patients (24.4% vs. 10.4%, p = 0.048). No associations were found between CARD15 mutations and family history, symptoms or CRC pathologic characteristics. CONCLUSIONS: The CARD15 R702W variant might be a predisposing factor to sporadic CRC in Portugal, particularly in patients under 60-years old and in female patients. This susceptibility appears to be linked with germline CARD15 mutations. Nevertheless, we have found no evidence that CARD15 mutations predict the pathologic characteristics of CRC