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Author summary Allostery in proteins is the property of highly specific responses to ligand binding at a distant site. To inform protocols of de novo drug design, it is fundamental to understand the impact of mutations on allosteric regulation and whether it can be predicted from evolutionary correlations. In this work we consider allosteric architectures artificially evolved to optimize the cooperativity of binding at allosteric and active site. We first characterize the emergent pattern of epistasis as well as the underlying mechanical phenomena, finding the four types of epistasis (Synergistic, Sign, Antagonistic, Saturation), which can be both short or long-range. The numerical evolution of these allosteric architectures allows us to benchmark Direct Coupling Analysis, a method which relies on co-evolution in sequence data to infer direct evolutionary couplings, in connection to allostery. We show that Direct Coupling Analysis predicts quantitatively point mutation costs but underestimates strong long-range epistasis. We provide an argument, based on a simplified model, illustrating the reasons for this discrepancy. Our analysis suggests neural networks as more promising tool to measure epistasis.

The jamming transition of non-spherical particles is fundamentally different from the spherical case. Non-spherical particles are hypostatic at their jamming points, while isostaticity is ensured in the case of the jamming of spherical particles. This structural difference implies that the presence of asphericity affects the critical exponents related to the contact number and the vibrational density of states. Moreover, while the force and gap distributions of isostatic jamming present power-law behaviors, even an infinitesimal asphericity is enough to smooth out these singularities. In a recent work (Brito et al 2018 Proc. Natl Acad. Sci. 115 11736–41), we have used a combination of marginal stability arguments and the replica method to explain these observations. We argued that systems with internal degrees of freedom, like the rotations in ellipsoids, or the variation of the radii in the case of the breathing particles fall in the same universality class. In this paper, we review comprehensively the results about the jamming with internal degrees of freedom in addition to the translational degrees of freedom. We use a variational argument to derive the critical exponents of the contact number, shear modulus, and the characteristic frequencies of the density of states. Moreover, we present additional numerical data supporting the theoretical results, which were not shown in the previous work.

Resumo: Este trabalho apresenta o desenvolvimento de um Sistema de Informação Geográfica (SIG) das instituições de ensino básico, fundamental e médio, tanto públicas como particulares da região do litoral norte do Rio Grande do Sul, Brasil. O texto relata as seguintes etapas: aquisição dos dados, construção do banco de dados georreferenciado, análise de algumas características das escolas (número de alunos, situação rural/urbana, escola indígena) e infraestrutura disponível (biblioteca, internet, quadra, pátio) e, finalmente, a representação visual da distribuição espacial das escolas e seus indicadores. A base espacial georreferenciada, contendo a localização das escolas, foi construída a partir das coordenadas geográficas fornecidas pela Secretaria Estadual de Educação e pela geocodificação através do ArcGis. A base de dados estatísticos foi coletada através do processamento dos microdados do Censo Escolar de 2018, do Instituto Nacional de Estudos e Pesquisas Educacionais Anísio Teixeira (INEP).

ABSTRACT:

This work presents the development of a Geographic Information System (GIS) for the analysis of basic and high school institutions, both public and private in the northern coast of Rio Grande do Sul, Brazil. The text reports the following steps: data acquisition, construction of the georeferenced database, analysis of some schools characteristics (number of students, rural / urban situation, indigenous school) and available infrastructure (library, internet, court, patio) and, finally, the visual representation of the spatial distribution of schools and their indicators. The georeferenced spatial base, containing the location of the schools, was built from the geographical coordinates provided by the State Department of Education and by geocoding through ArcGis. The statistical database was collected through the processing of microdata from the 2018 School Census, from National Institute for Educational Studies and Research "Anísio Teixeira" (INEP).

BACKGROUND: Despite the association between cardiovascular diseases and periodontitis, there are scarce data on the impact of oral health in the dietary intake of patients with coronary artery disease (CAD). The aim of this study was to assess the association between dietary intake with periodontitis and present teeth in individuals with stable CAD. METHODS: This cross-sectional study included 115 patients with stable CAD (76 males, aged 61.0 +/- 8.3 years) who were under cardiovascular care in an outpatient clinic for at least 3 months. Dietary intake was recorded applying a food frequency questionnaire previously validated. Periodontal examinations were performed by two calibrated examiners in six sites per tooth from all present teeth. Blood samples were collected to determine serum levels of lipids. Multivariable logistic and linear regression models were fitted to evaluate the association between dietary outcomes and oral health variables. RESULTS: Individuals with periodontitis had significantly higher percentage of total energy intake from fried foods, sweets, and beans, and also had lower consumption of fruits than those without periodontitis. Presence of periodontitis was associated with lower percentage of individuals who reached the nutritional recommendation of monounsaturated fatty acids and higher blood concentration of triglycerides. Having a greater number of present teeth (>/=20 teeth) was associated with higher intake of fibers and total calories. CONCLUSION: In patients with stable CAD, the presence of periodontitis and tooth loss were associated with a poor dietary intake of nutrients and healthy foods, which are important for cardiovascular prevention.

The aim of this study was to assess the occurrence of selfreported dentin hypersensitivity (DH) and its risk indicators in adolescents from a southern Brazilian city. 736 students (1519 years old) were randomly selected from 20 public and private schools in the city of Passo Fundo, Brazil. DH was assessed through the answers on a Likert scale to the question: "Do you have tooth sensitivity?".Participants underwent a clinical examination in which present teeth were counted, and answered an interview based on a structured questionnaire on sociode mographic information, history of dental bleaching, orthodontic treatment and oral health habits. The dependent variable (DH) was dichotomized at the point where hypersen sitivity occurs fairly often or always. Data were analyzed by multivariable logistic regression, including demographic, health history, socioeconomic and behavioral variables. Results: 556 (75.5%) subjects reported having sensitive teeth never, rarely or sometimes, while 180 (24.5%) reported having sensitive teeth fairly often or always. In the final model, number of present teeth, age, skin color, flossing, smoking, bleaching and orthodontic history were not associated with selfreported DH. Females showed significantly greater chance of having DH than males [odds ratio (OR)=1.91; 95% confidence interval (95%CI) 1.342.72]. The likelihood of DH in students at public schools was 63% higher than in those at private schools (OR=1.63 95%, CI 1.012.75). DH is a common perception among adolescents and is associated with female gender and studying at public schools.

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