Single-species fragmentation: the role of density-dependent feedbacks

Internal feedbacks are commonly present in biological populations and can play a crucial role in the emergence of collective behavior. We consider a generalization of Fisher-KPP equation to describe the temporal evolution of the distribution of a single-species population. This equation includes the elementary processes of random motion, reproduction and, importantly, nonlocal interspecific competition, which introduces a spatial scale of interaction. Furthermore, we take into account feedback mechanisms in diffusion and growth processes, mimicked through density-dependencies controlled by exponents $\nu$ and $\mu$, respectively. These feedbacks include, for instance, anomalous diffusion, reaction to overcrowding or to rarefaction of the population, as well as Allee-like effects. We report that, depending on the dynamics in place, the population can self-organize splitting into disconnected sub-populations, in the absence of environment constraints. Through extensive numerical simulations, we investigate the temporal evolution and stationary features of the population distribution in the one-dimensional case. We discuss the crucial role that density-dependency has on pattern formation, particularly on fragmentation, which can bring important consequences to processes such as epidemic spread and speciation

PASSIOMA: Exploring Expressed Sequence Tags during Flower Development in Passiflora spp.

The genus Passiflora provides a remarkable example of floral complexity and diversity. The extreme variation of Passiflora flower morphologies allowed a wide range of interactions with pollinators to evolve. We used the analysis of expressed sequence tags (ESTs) as an approach for the characterization of genes expressed during Passiflora reproductive development. Analyzing the Passiflora floral EST database (named PASSIOMA), we found sequences showing significant sequence similarity to genes known to be involved in reproductive development such as MADS-box genes. Some of these sequences were studied using RT-PCR and in situ hybridization confirming their expression during Passiflora flower development. The detection of these novel sequences can contribute to the development of EST-based markers for important agronomic traits as well as to the establishment of genomic tools to study the naturally occurring floral diversity among Passiflora species

Sparse Higher Order ?ech Filtrations

For a finite set of balls of radius r, the k-fold cover is the space covered by at least k balls. Fixing the ball centers and varying the radius, we obtain a nested sequence of spaces that is called the k-fold filtration of the centers. For k = 1, the construction is the union-of-balls filtration that is popular in topological data analysis. For larger k, it yields a cleaner shape reconstruction in the presence of outliers. We contribute a sparsification algorithm to approximate the topology of the k-fold filtration. Our method is a combination and adaptation of several techniques from the well-studied case k = 1, resulting in a sparsification of linear size that can be computed in expected near-linear time with respect to the number of input points

El papel del movimiento "economía y humanismo" y de la SAGMACS en Brasil en la construcción de un nuevo método de proyectación urbana

El tema central de la presente propuesta es el análisis de la experiencia proyectual desarrollada a través de la SAGMACS (Sociedade para Análise Gráfica e Mecanográfica Aplicadas aos Complexos Sociais), creada por el padre Lebret en Brasil en 1947 y que representa un ‘punto de inflexión en la experiencia de un nuevo método de proyectación urbana’, un cambio en la manera de proyectar, planear y solucionar los problemas urbanos de las ciudades, a través de una elaboración continuada de una metodología de investigación urbano-regional centrada en el bien común y en el ascenso de la vida humana asociada al desarrollo económico, estableciendo nuevos caminos para el desarrollo y la organización territorial de importantes ciudades en el país como Recife, Rio de Janeiro, São Paulo y Belo Horizonte.The main theme of this research is the analysis of the projectual experience that was carried out within the SAGMACS (Sociedade para Análise Gráfica e Mecanográfica Aplicadas aos Complexos Sociais /Society for Graphic and Mecanographic Analysis Applied to Social Complexes) created by Lebret in Brazil in 1947 and which represents a 'turning point in urban planning’s method’, a change in the way of designing, planning and solving urban problems of cities through continued development of a methodology of urban-regional research focused on the common good and growth of human life associated to economical development, establishing new ways for the development and territorial organization of important cities in the country like Recife, São Paulo and Belo Horizonte.Peer Reviewe

Rhinophyma: analysis of the shave excision technique

INTRODUCTION: The rhinophyma is an extremely stigmatizing condition for a patient. The first descriptions of this disease dates back to the time of Hippocrates, which was popular known as alcoholic nose or nasal elephantiasis is responsible for generating a huge deformity in the nose. This deformity derives from a process of hyperplasia and hypertrophy of the sebaceous glands in nasal skin associated with fibrosis and dilated local blood vessels and connective tissue. Surgery is considered the treatment of choice for aesthetic improvement of the injury. METHODS: This was a retrospective study based on analysis of results from 11 patients (10 men and 1 woman) who underwent treatment for rhinophyma between January 2010 to January 2016 at the Plastic Surgery Service of the Teaching Hospital of Federal University of Juiz de Fora and Clinical Plastic Center. RESULTS: Of 11 patients who underwent surgery, a 72-year-old man had basal expansive invasive carcinoma with positive surgical margins after pathological examination of the surgical specimen, however, the patient had pathological free margins after reoperation. Other 3 patients had hypercromy in the intervention region during the immediate postoperative. CONCLUSION: Despite technological advances, the removal of the injury with a cold scalpel technique and the use of postoperative dressings are highly efficient, when combined, provide excellent aesthetic results with low complication rates and high rates of patients' satisfaction, whom mostly had improvement in quality of life after the procedure

A Genomic Approach to Study Anthocyanin Synthesis and Flower Pigmentation in Passionflowers

Most of the plant pigments ranging from red to purple colors belong to the anthocyanin group of flavonoids. The flowers of plants belonging to the genus Passiflora (passionflowers) show a wide range of floral adaptations to diverse pollinating agents, including variation in the pigmentation of floral parts ranging from white to red and purple colors. Exploring a database of expressed sequence tags obtained from flower buds of two divergent Passiflora species, we obtained assembled sequences potentially corresponding to 15 different genes of the anthocyanin biosynthesis pathway in these species. The obtained sequences code for putative enzymes are involved in the production of flavonoid precursors, as well as those involved in the formation of particular (“decorated”) anthocyanin molecules. We also obtained sequences encoding regulatory factors that control the expression of structural genes and regulate the spatial and temporal accumulation of pigments. The identification of some of the putative Passiflora anthocyanin biosynthesis pathway genes provides novel resources for research on secondary metabolism in passionflowers, especially on the elucidation of the processes involved in floral pigmentation, which will allow future studies on the role of pigmentation in pollinator preferences in a molecular level

The Shape of Species Abundance Distributions Across Spatial Scales

Species abundance distributions (SADs) describe community structure and are a key component of biodiversity theory and research. Although different distributions have been proposed to represent SADs at different scales, a systematic empirical assessment of how SAD shape varies across wide scale gradients is lacking. Here, we examined 11 empirical large-scale datasets for a wide range of taxa and used maximum likelihood methods to compare the fit of the logseries, lognormal, and multimodal (i.e., with multiple modes of abundance) models to SADs across a scale gradient spanning several orders of magnitude. Overall, there was a higher prevalence of multimodality for larger spatial extents, whereas the logseries was exclusively selected as best fit for smaller areas. For many communities the shape of the SAD at the largest spatial extent (either lognormal or multimodal) was conserved across the scale gradient, despite steep declines in area and taxonomic diversity sampled. Additionally, SAD shape was affected by species richness, but we did not detect a systematic effect of the total number of individuals. Our results reveal clear departures from the predictions of two major macroecological theories of biodiversity for SAD shape. Specifically, neither the Neutral Theory of Biodiversity (NTB) nor the Maximum Entropy Theory of Ecology (METE) are able to accommodate the variability in SAD shape we encountered. This is highlighted by the inadequacy of the logseries distribution at larger scales, contrary to predictions of the NTB, and by departures from METE expectation across scales. Importantly, neither theory accounts for multiple modes in SADs. We suggest our results are underpinned by both inter- and intraspecific spatial aggregation patterns, highlighting the importance of spatial distributions as determinants of biodiversity patterns. Critical developments for macroecological biodiversity theories remain in incorporating the effect of spatial scale, ecological heterogeneity and spatial aggregation patterns in determining SAD shape.Peer reviewe

Exploring the role of auxin in the androgynophore movement in passiflora

The flowers of the species belonging to the genus Passiflora show a range of features that are thought to have arisen as adaptations to different pollinators. Some Passiflora species belonging to the subgenus Decaloba sect. Xerogona, show touch-sensitive motile androgynophores. We tested the role of auxin polar transport in the modulation of the androgynophore movement by applying auxin (IAA) or an inhibitor of auxin polar transport (NPA) in the flowers. We recorded the movement of the androgynophore during mechano-stimulation and analyzed the duration, speed, and the angle formed by the androgynophore before and after the movement, and found that both IAA and NPA increase the amplitude of the movement in P. sanguinolenta. We hypothesize that auxin might have a role in modulating the fitness of these Decaloba species to different pollination syndromes and demonstrate that an interspecific hybrid between insect- and hummingbird-pollinated Xerogona species present a heterosis effect on the speed of the androgynophore383301307CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPES

Plano centro cidadão: por um espaço urbano integrado

O Plano Centro Cidadão tem por objetivo o desenvolvimento de estudos urbanos para o “Centro Continental do Recife”, promovendo uma revisão das práticas urbano-arquitetônicas e das políticas para os espaços públicos, renovando os conceitos e valores urbanos da cidade que implementem a qualidade de vida cidadã, através de propostas de diretrizes urbanísticas para o território. Um dos principais desafios do Plano é o desenvolvimento de um processo de trabalho colaborativo. O objetivo do presente artigo é apresentar os conceitos norteadores do Plano, a metodologia empregada para o desenvolvimento dos trabalhos e o processo de colaboração social como etapa importante para a construção de um planejamento integrado.The objective of the plan entitled Centro Cidadão (A center for citizens) is to develop urban studies for a downtown area in the city of Recife known as its continental center. The process involves critical review of current urban design practices and politics regarding public spaces, leading to updated concepts and urban values that might improve the quality of life in the city, to be implemented through specific design guidelines. One of the Plan’s biggest challenges is to carry a collaborative work process. The goal of this paper is to present the guiding concepts of the Plan and its methodology, particularly its collaborative process, an important aspect towards achieving integrated urban planning