Regeneração natural de castanheira da Amazônia e interação de seu crescimento inicial com atributos do solo e luz.

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Estrutura e distribuição espacial de andirobeiras (Carapa spp.) em floresta de várzea do Estuário Amazônico.

O objetivo geral deste trabalho foi avaliar se a densidade de ocorrência de andirobeiras é dependente da distância do rio Amazonas, analisando sua distribuição espacial e a estrutura diamétrica da população em um trecho de floreta de várzea no Estado do Amapá. Esse trabalho faz parte do projeto Florestam (Ecologia e manejo florestal para uso múltiplo de várzeas do estuário amazônico) e foi desenvolvido em uma área de proteção ambiental (APA) de 136,59 ha, localizada no Distrito da Fazendinha, município de Macapá - AP (00°03’04,24”S e 51º07’42,72”W). Foram lançados 3 transectos perpendiculares à margem do rio Amazonas, distanciados entre si a cada 500 m, para orientar no direcionamento e localização das árvores

The CP-conserving 2HDM after the 8 TeV run

We confront the most common CP-conserving 2HDM with the LHC data analysed so far while taking into account all previously available experimental data. A special allowed corner of the parameter space is analysed - the so-called wrong-sign scenario where the Higgs coupling to down-type quarks changes sign relative to the Standard Model while the coupling to the massive vector bosons does not.Comment: 6 pages, 2 figures, to appear in the proceedings of the 22nd International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS 2014), 28 April - 2 May 2014 Warsaw (Poland

The Wrong Sign limit in the 2HDM

A sign change in the Higgs couplings to fermions and massive gauge bosons is still allowed in the framework of two-Higgs doublet models (2HDM). In this work we discuss the possible sign changes in the Higgs couplings to fermions and gauge bosons, while reviewing the status of the 8-parameter CP-conserving 2HDM after the Large Hadron Collider 8 TeV run.Comment: 6 pages, 3 figures. Proceedings of the Second Annual Conference on Large Hadron Collider Physics, Columbia University, New York, U.S.A, June 2-7, 2014. arXiv admin note: text overlap with arXiv:1407.439

Mating behaviour and reproductive output in insecticide-resistant and -susceptible strains of the maize weevil (\u3ci\u3eSitophilus zeamais\u3c/i\u3e)

Insecticide resistance is a broadly recognised and well-studied management problem resulting from intensive insecticide use, which also provides useful evolutionary models of newly adapted phenotypes to changing environments. Two common assumptions in such models are the existence of fitness costs associated with insecticide resistance, which will place the resistant individuals at a disadvantage in insecticide-free environments, and the prevalence of random mating among insecticide-resistant and -susceptible individuals. However, cases of insecticide resistance lacking apparent fitness disadvantages do exist impacting the evolution and management of insecticide resistance. Assortative mating, although rarely considered, may also favour the evolution and spread of insecticide resistance. Thus, the possible existence of both conditions in the maize weevil (Sitophilus zeamais), a key pest of stored cereals, led to the assessment of the mating behaviour and reproductive fitness of insecticide-resistant and -susceptible weevil strains and their reciprocal crosses. The patterns of female and male mating choice also were assessed. Although mating behaviour within and between weevil strains was similar without mate choice, mating within the resistant strain led to higher reproductive output than within the susceptible strain; inter-strain matings led to even higher fertility. Thus, no apparent fitness cost associated with resistance seems to exist in these weevils, favouring the evolution of this phenotype that is further aided by the higher fertility of inter-strain matings. Mate choice reduced latency to mate and no inter-strain preference was detected, but female weevils were consistent in their mate selection between 1st and 2nd matings indicating existence of female mating preference among maize weevils. Therefore, if female mate selection comes to favour trait(s) associated with insecticide resistance, higher reproductive fitness will be the outcome of such matings favouring the evolution and spread of insecticide resistance among maize weevil populations reverting into a management concern

Florística e fitossociologia em áreas de manejo de açaizais no estuário amazônico.

Este estudo teve como objetivo analisar a composição florística e a fitossociologia em três regiões do estuário amazônico em que é praticado o manejo de açaizais nativos. Nas regiões foram instaladas 30 parcelas de 0,5 ha e amostradas todas as espécies arbóreas e palmeiras com DAP ? 5 cm, mediu-se também a circunferência a altura do peito (CAP) com fita métrica de precisão de 1mm. Foram inventariados 10821 indivíduos, representados por 114 espécies, 96 gêneros e 33 famílias. As famílias mais representativas foram Arecaceae (9 espécies e 8007 indivíduos), seguida por Rubiaceae (2 espécies e 522 indivíduos),Myristicaceae (1 espécie e 268 indivíduos), Malvaceae (10 espécies e 264 indivíduos) e Euphorbiaceae (4 espécies e 247 indivíduos). Constatou-se que a riqueza nas áreas de manejo inventariadas permaneceu alta apesar da pressão antrópica que essas áreas sofrem

Optimal configuration of microstructure in ferroelectric materials by stochastic optimization

An optimization procedure determining the ideal configuration at the microstructural level of ferroelectric (FE) materials is applied to maximize piezoelectricity. Piezoelectricity in ceramic FEs differ significantly from that of single crystals because of the presence of crystallites (grains) possessing crystallographic axes aligned imperfectly. The piezoelectric properties of a polycrystalline (ceramic) FE is inextricably related to the grain orientation distribution (texture). The set of combination of variables, known as solution space, which dictates the texture of a ceramic is unlimited and hence the choice of the optimal solution which maximizes the piezoelectricity is complicated. Thus a stochastic global optimization combined with homogenization is employed for the identification of the optimal granular configuration of the FE ceramic microstructure with optimum piezoelectric properties. The macroscopic equilibrium piezoelectric properties of polycrystalline FE is calculated using mathematical homogenization at each iteration step. The configuration of grains characterised by its orientations at each iteration is generated using a randomly selected set of orientation distribution parameters. Apparent enhancement of piezoelectric coefficient $d_{33}$ is observed in an optimally oriented BaTiO$_3$ single crystal. A configuration of crystallites, simultaneously constraining the orientation distribution of the c-axis (polar axis) while incorporating ab-plane randomness, which would multiply the overall piezoelectricity in ceramic BaTiO$_{3}$ is also identified. The orientation distribution of the c-axes is found to be a narrow Gaussian distribution centred around ${45^\circ}$. The piezoelectric coefficient in such a ceramic is found to be nearly three times as that of the single crystal.Comment: 11 pages, 7 figure