Local heuristics and the emergence of spanning subgraphs in complex networks

We study the use of local heuristics to determine spanning subgraphs for use in the dissemination of information in complex networks. We introduce two different heuristics and analyze their behavior in giving rise to spanning subgraphs that perform well in terms of allowing every node of the network to be reached, of requiring relatively few messages and small node bandwidth for information dissemination, and also of stretching paths with respect to the underlying network only modestly. We contribute a detailed mathematical analysis of one of the heuristics and provide extensive simulation results on random graphs for both of them. These results indicate that, within certain limits, spanning subgraphs are indeed expected to emerge that perform well in respect to all requirements. We also discuss the spanning subgraphs' inherent resilience to failures and adaptability to topological changes

Probabilistic heuristics for disseminating information in networks

We study the problem of disseminating a piece of information through all the nodes of a network, given that it is known originally only to a single node. In the absence of any structural knowledge on the network other than the nodes' neighborhoods, this problem is traditionally solved by flooding all the network's edges. We analyze a recently introduced probabilistic algorithm for flooding and give an alternative probabilistic heuristic that can lead to some cost-effective improvements, like better trade-offs between the message and time complexities involved. We analyze the two algorithms both mathematically and by means of simulations, always within a random-graph framework and considering relevant node-degree distributions

Quantum density anomaly in optically trapped ultracold gases

We show that the Bose-Hubbard Model exhibits an increase in density with temperature at fixed pressure in the regular fluid regime and in the superfluid phase. The anomaly at the Bose-Einstein condensate is the first density anomaly observed in a quantum state. We propose that the mechanism underlying both the normal phase and the superfluid phase anomalies is related to zero point entropies and ground state phase transitions. A connection with the typical experimental scales and setups is also addressed. This key finding opens a new pathway for theoretical and experimental studies of water-like anomalies in the area of ultracold quantum gases

Two novel evolutionary formulations of the graph coloring problem

We introduce two novel evolutionary formulations of the problem of coloring the nodes of a graph. The first formulation is based on the relationship that exists between a graph's chromatic number and its acyclic orientations. It views such orientations as individuals and evolves them with the aid of evolutionary operators that are very heavily based on the structure of the graph and its acyclic orientations. The second formulation, unlike the first one, does not tackle one graph at a time, but rather aims at evolving a `program' to color all graphs belonging to a class whose members all have the same number of nodes and other common attributes. The heuristics that result from these formulations have been tested on some of the Second DIMACS Implementation Challenge benchmark graphs, and have been found to be competitive when compared to the several other heuristics that have also been tested on those graphs.Comment: To appear in Journal of Combinatorial Optimizatio

Post-activation Potentiation In Propulsive Force After Specific Swimming Strength Training

We investigated whether a conditioning activity (8x12.5m with 2.5min-interval using both hand paddles and parachute) induced post-activation potentiation in swimming propulsive force and whether a swimmer's force level affected a post-activation potentiation response. 8 competitive swimmers (5 males and 3 females, age: 18.4 +/- 1.3 years; IPS=796 +/- 56) performed a 10s maximum tethered swimming test 8 and 4min before (the highest value was considered as PRE), and 2.5 and 6.5min after (POST1 and POST2, respectively) the conditioning activity. Rate of force development was not affected, but peak force in POST1 (p=0.02) and impulse in both POST1 (p=0.007) and POST2 (p=0.004) were reduced. Possibly the conditioning activity induced greater fatigue than post-activation potentiation benefits. For instance, the number of repetitions might have been excessive, and rest intervals between the conditioning activity and POST1 and POST2 were possibly too short. There were positive correlations between PRE peak force and changes in peak force and rate of force development. Although conditioning activity was detrimental, positive correlations suggest that weaker swimmers experience a deterioration of performance more than the stronger ones. This conditioning activity is not recommended for swimmers with the current competitive level before a competitive event.37431331

Caracterização molecular de Potyvirus que infectam maracujazeiro (Passiflora sp.) no estado da Bahia.

Inúmeras doenças afetam a cultura do maracujazeiro no Brasil, causando grandes prejuízos de ordem econômica, sendo que a virose do endurecimento dos frutos é uma das mais limitantes à produção. Essa doença sempre esteve associada a uma única espécie de Potyvirus, o Passionfruit woodiness virus (PWV). Porém, estudos conduzidos ao longo dos anos demonstraram que mais duas espécies de Potyvirus, o Cowpea aphid-borne mosaicvirus (CABMV) e o East asian passiflora virus (EAPV) também podem causar a mesma doença

Potential of plant products as protectants of stored maize against Sitophilus zeamais Motschulsky (Coleoptera:Curculionidae)

Laboratory studies were carried out to evaluate the effects of some formulations from Mentha pulegium, Lonchocarpus sericeus, Daphne gnidium, Laurus nobilis, Momordica charantia, Nerium oleander and Ptaeroxylon obliquum as protectants against adult insects of Sitophilus zeamais on stored maize. The dusts from leaves of L. nobilis at 30% w/w caused 86% mortality and reduced F1 progeny emergence up to 57%. At the same concentration, dusts of pink flowers from N. oleander and leaves from L. sericeus reduced the F1 progeny up to 68% and 70%, reduced the developmental index and prolonged the developmental period by 4 and 6 d, respectively. The suspensions (2% v/v) from M. charantia, N. oleander and P. obliquum reduced the F1 progeny emergence up to 58, 91 and 94% and the number of holes in grains by 75, 91 and 97%, respectively. The methanol extracts were more effective than n-hexane extracts and affected the F1 progeny emergence and the developmental index. Keywords: Sitophilus zeamais, Botanical insecticides, Repellence, Insect control agents

Informações técnicas para o cultivo do feijoeiro-comum na Região Central-Brasileira: 2012-2014.

Socioeconomia; Exigências climáticas e épocas de semeadura; Manejo do solo; Correção e fertilização do solo; Fixação biológica de nitrogênio - FBN; Cultivares; Implantação da lavoura; Manejo de plantas daninhas; Manejo da irrigação; Manejo integrado de doenças; Manejo integrado de pragas; Colheita; Beneficiamento e armazenamento; Recomendações técnicas para a produção de sementes do feijoeiro-comum.bitstream/item/61388/1/seriedocumentos-272.pd

Waterlike density anomaly in fermions

In this work we explore the one-dimensional extended Hubbard model as a fluid system modelling liquid phases of different densities. This model naturally displays two length scales of interaction, which are connected with waterlike anomalies. We analyze the density anomaly as a function of the model parameters, namely the hopping, on-site and first neighbor interactions. We show that this anomaly is present for a wide range of model parameters and is connected to a ground-state liquid-liquid critical point.Comment: 15 pages, 9 figure