Complexity in surfaces of densest packings for families of polyhedra

Packings of hard polyhedra have been studied for centuries due to their mathematical aesthetic and more recently for their applications in fields such as nanoscience, granular and colloidal matter, and biology. In all these fields, particle shape is important for structure and properties, especially upon crowding. Here, we explore packing as a function of shape. By combining simulations and analytic calculations, we study three 2-parameter families of hard polyhedra and report an extensive and systematic analysis of the densest packings of more than 55,000 convex shapes. The three families have the symmetries of triangle groups (icosahedral, octahedral, tetrahedral) and interpolate between various symmetric solids (Platonic, Archimedean, Catalan). We find that optimal (maximum) packing density surfaces that reveal unexpected richness and complexity, containing as many as 130 different structures within a single family. Our results demonstrate the utility of thinking of shape not as a static property of an object in the context of packings, but rather as but one point in a higher dimensional shape space whose neighbors in that space may have identical or markedly different packings. Finally, we present and interpret our packing results in a consistent and generally applicable way by proposing a method to distinguish regions of packings and classify types of transitions between them.Comment: 16 pages, 8 figure

Análise logística e as expectativas dos empresários locais na implantação do Porto Espadarte para o desenvolvimento regional / Logistic analysis and the expectations of local businessman about the implementation of Porto Espadarte for regional development

O desenvolvimento portuário tem sido utilizado como importante elemento estratégico para o crescimento econômico em várias partes do mundo, sendo importante vetor de impactos econômico e sócio-ambientais em seu entorno sendo ambiente propício a forte geração de emprego e renda no nordeste do Pará. Através desta pesquisa sugere-se a realização de novos estudos, projetos e ações em diversas secretarias, com parcerias de órgãos públicos e privados, que visem o desenvolvimento local em consonância com a sustentabilidade econômica

Avaliação de práticas de gestão do conhecimento no Exército Brasileiro: um estudo de caso no complexo militar do Pinheirinho: Assessment of knowledge management practices in the Brazilian Army: a case study in the Pinheirinho Military complex

As dificuldades surgidas devido ao aumento da velocidade das informações no mundo moderno são algo a ser manejado em qualquer instituição da atualidade que esteja preocupada com seu sucesso, seja no setor privado ou no público. A Gestão do Conhecimento (GC) e suas práticas podem auxiliar nesta jornada, facilitando a economia de recursos nos setores mais diversos. O Exército Brasileiro (EB), enquanto instituição nacional permanente, tem características únicas que também o fazem demandar da GC no seu dia-a-dia. Neste trabalho, foi realizada uma análise das práticas de GC em um grupo de unidades do Exército Brasileiro, baseada no trabalho de Batista e Quandt (2015), verificando-se os aspectos “estágio de implantação” e “alcance”. As práticas abordadas foram divididas conforme as dimensões da GC propostas por Misra (2007), a saber: gestão de recursos humanos (Pessoas), processos organizacionais (Processos) e base tecnológica e funcional (Tecnologia). O instrumento de pesquisa foi respondido por 207 pessoas, com escolaridade mínima de ensino médio completo, participantes de todas as Organizações Militares (OM) do complexo militar do bairro Pinheirinho, na cidade de Curitiba, Paraná. A pesquisa caracterizou-se como “exploratória-descritiva”, na modalidade “estudo de caso” e subtipo “estudo de casos múltiplos”, com viés quantitativo. O trabalho realizado pode ser aplicado em outras OM, instituições públicas, empresas privadas ou mesmo em partes destes estabelecimentos, a fim de se diagnosticar a Gestão do Conhecimento, de se proporem medidas de aprimoramento de suas práticas e, por consequência, melhorar a eficiência funcional dos locais analisados

Role of short-range order and hyperuniformity in the formation of band gaps in disordered photonic materials

We study photonic band gap formation in two-dimensional high-refractive-index disordered materials where the dielectric structure is derived from packing disks in real and reciprocal space. Numerical calculations of the photonic density of states demonstrate the presence of a band gap for all polarizations in both cases. We find that the band gap width is controlled by the increase in positional correlation inducing short-range order and hyperuniformity concurrently. Our findings suggest that the optimization of short-range order, in particular the tailoring of Bragg scattering at the isotropic Brillouin zone, are of key importance for designing disordered PBG materials

Prediction of new gene products and characterization of hypothetical proteins of Bifidobacterium breve DS15-17 In Silico / Predição de novos produtos gênicos e caracterização de proteínas hipotéticas de Bifidobacterium breve DS15-17 In Silico

The representation of the gene content of an organism is impacted by several factors, ranging from sampling to sequencing and then the genome assembly task. The genome assembly process can generate errors that are related to insufficient coverage in the data set, an inadequate assembly methodology, and finally, errors related to the limitation of the assembly software used. Thus, some genes remain unidentified both in complete and draft genomes, this incomplete gene knowledge impacts on several organisms, mainly of medical and industrial interest, such as Bifidobacterium breve, a Gram-positive bacterium, found in the gastrointestinal microbiota of mammals, including humans, and has beneficial probiotic activities. Therefore, the objective of this work is to identify the new gene products not represented in the genome of Bifidobacterium breve DS15-17 using the raw reads of this organism. The reads were produced from the sequencing with the Illumina MiSeq platform. PAN2HGENE software was used to identify new gene products. After the analysis, 44 new gene products were identified, 26 with described function and 18 hypothetical proteins. The hypothetical proteins identified were analyzed in the ProtoNet and Superfamily databases

Evaluation of the variability of compressive strength parallel to the fibers of hardwood species

Wood has several advantages as structural material. For this use to be applied in a safe way, it is necessary to know the statistical behavior of the mechanical properties. Some works and normative codes, such as the “Brazilian timber standard” (as well as its review project), accepts a normal distribution model for determining the characteristic value of compressive strength parallel to wood fiber, with the adoption of a coefficient of variation for this property equal to 18 %. This work evaluates the distribution model of compressive strength parallel to the fibers, as well as the coefficient of variation of this property. Tests and statistical treatment were performed in compression parallel to the fibers for 7 species of hardwood commonly found in Brazil. It was observed that the compressive strength of wood actually follows a normal distribution, and the adoption of an average coefficient of variation equal to 18 % is acceptable and in favor of safety.&nbsp