A one-dimensional Keller-Segel equation with a drift issued from the boundary

We investigate in this note the dynamics of a one-dimensional Keller-Segel type model on the half-line. On the contrary to the classical configuration, the chemical production term is located on the boundary. We prove, under suitable assumptions, the following dichotomy which is reminiscent of the two-dimensional Keller-Segel system. Solutions are global if the mass is below the critical mass, they blow-up in finite time above the critical mass, and they converge to some equilibrium at the critical mass. Entropy techniques are presented which aim at providing quantitative convergence results for the subcritical case. This note is completed with a brief introduction to a more realistic model (still one-dimensional).

Les premiers lecteurs de Walras en Russie (1890-1919)

Cet article offre la première chronologie des lecteurs de Walras en Russie, entre 1890 et 1919. Ce panorama de la pensée économique russe est le résultat de recherches originales effectuées dans des bibliothèques en Russie, ainsi que quelques fonds d'archives. La plupart de ces informations sont en soi inédites. Elles ne constituent toutefois que des matériaux pour de subséquentes recherches, qui sont esquissées dans le commentaire final de cet article.

The effect of different proportions of males and females over the Chrysomya albiceps (Wiedemann 1819) (Diptera, Calliphoridae) biotic potential and longevity under laboratory conditions

Chrysomya albiceps specimens were derived from colonies kept under laboratory conditions. The oviposition period, total number of eggs-mass and the weight of the eggs-mass (average/female) presented significant differences between colonies regarding the sexual ratio of 1male/1female (situation I), when compared to the other ratios (1male/3female, situation II), (1male/5female, situation III), (3male/1female, situation IV) and (5 male/1female, situation V). It was ascertained that the increase in the proportion of females, resulted in higher weight and greater number of ovipositions and lenghtening of the period of oviposition, leads to a decrease in their lifespan.

Temperature requirements of Chrysomya albiceps (Wiedemann, 1819) (Diptera, Calliphoridae) under laboratory conditions

Chrysomya albiceps specimens were obtained from colonies established with larvae and adults collected at the Federal Rural University in Rio de Janeiro, Seropédica, State of Rio de Janeiro. The larval stage of C. albiceps was allowed to develop in climatic chambers at temperatures of 18, 22, 27 and 32ºC, and the pupal stage was allowed to develop at 22, 27 and 32ºC (60 ± 10% RH and 14 hr photoperiod). The duration and viability of the larval stage of C. albiceps at 18, 22, 27 and 32ºC were 21.30, 10.61, 5.0 and 4.0 days and 76.5, 88.5, 98.5 and 99.5%, respectively, with mean mature larval weights of 45.16, 81.86, 84.35 and 70.53 mg, respectively. Mean duration and viability of the pupal stage at 22, 27 and 32ºC were 9.36, 4.7 and 3.0 days and 93.8, 100 and 100%, respectively. The basal temperature for the larval and pupal stage and for the larval and adult phase were 15.04, 17.39 and 15.38ºC, corresponding to 65.67, 44.15 and 114.23 DD.

Refined asymptotics for the subcritical Keller-Segel system and related functional inequalities

We analyze the rate of convergence towards self-similarity for the subcritical Keller-Segel system in the radially symmetric two-dimensional case and in the corresponding one-dimensional case for logarithmic interaction. We measure convergence in Wasserstein distance. The rate of convergence towards self-similarity does not degenerate as we approach the critical case. As a byproduct, we obtain a proof of the logarithmic Hardy-Littlewood-Sobolev inequality in the one dimensional and radially symmetric two dimensional case based on optimal transport arguments. In addition we prove that the onedimensional equation is a contraction with respect to Fourier distance in the subcritical case.

Genetic and morphological characterisation of a new species of the genus Hysterothylacium (Nematoda) from Paralichthys isosceles Jordan, 1890 (Pisces: Teleostei) of the Neotropical Region, state of Rio de Janeiro, Brazil

Taking into account the difficulties of taxonomic identification of larval anisakid nematodes based on morphological characters, genetic analyses were performed, together with those usually applied, in order to identify anisakid larvae found in the flounder Paralichthys isosceles from the littoral of the state of Rio de Janeiro, Brazil. The analysis of 1,820 larvae revealed a new species, similar to Hysterothylacium MD, Hysterothylacium 2, Hysterothylacium KB and Hysterothylacium sp regarding the absence of the larval tooth, an excretory pore situated below the nerve ring level, and slender lateral alae. Moreover, the new species differs from Hysterothylacium fortalezae and Hysterothylacium reliquens with regard to the number and size of spines present on the tail end and from Hysterothylacium patagonicus by the absence of interlabia. The maximum parsimony and neighbour joining tree topologies based on the 18S ribosomal DNA gene, complete internal transcribed spacer region and cytochrome oxidase 2 (COII) gene demonstrated that the Brazilian larvae belong to Raphidascarididae and represent a unique genetic entity, confirmed as a new Hysterothylacium species. Furthermore, the new species presents COII genetic signatures and shares polymorphisms with Raphidascarididae members. This is the first description of a new anisakid species from Brazil through the integration of morphological and molecular taxonomy data.

Coulier, Paul-Jean (1824-1890) : a precursor in the history of fingermark detection and their potential use for identifying their source (1863)

An online copy of a 1863 French book, The Scientific and Industrial Year (English translation of the title), that predates other historically significant writings about fingerprints suggests the use of iodine stains to reproduce papillary lines of the skin and suggests the feasibility of identifying suspects by touch. It also suggests the use of a magnifying glass for comparing those impressions whose origins need to be determined.

Registros noticiosos sobre a escola profissional de enfermeiros e enfermeiras na revista "O Brazil-Médico", 1890-1922

Estudo histórico descritivo com o objetivo de identificar registros noticiosos sobre a Escola de Enfermagem Alfredo Pinto, antiga Escola Profissional de Enfermeiros e Enfermeiras (EPEE), veiculadas na revista mencionada no período referido. A metodologia utilizada foi a análise documental como técnica de pesquisa. A revista foi publicada de forma ininterrupta durante esse período de 32 anos e 1.632 exemplares foram consultados. Foram encontradas 16 notícias alusivas à EPEE, ao Hospital Nacional de Alienados, à Enfermagem e Cursos de Enfermagem. Desse total, apenas cinco notícias referiam-se diretamente à EPEE. Analisando seu conteúdo despontam duas idéias fundamentais: 1) a EPEE teve duas inaugurações, em 1897 e 1906, o que ratifica o Decreto de criação em 27/09/1890; e, 2) a dificuldade de operacionalização da EPEE, àquela época, em virtude da baixa qualificação dos candidatos a alunos.