Levantamento, catalogação e zoneamento de pragas associadas a essências florestais plantadas no Brasil.

EVINCI. Resumo

The muonic longitudinal shower profiles at production

In this paper the longitudinal profile of muon production along the shower axis is studied. The characteristics of this distribution is investigated for different primary masses, zenith angles, primary energies, and different high energy hadronic models. It is found that the shape of this distribution displays universal features similarly to what is known for the electromagnetic profile. The relation between the muon production distribution and the longitudinal electromagnetic evolution is also discussed

Quantum field theory solution for a short-range interacting SO(3) quantum spin-glass

We study the quenched disordered magnetic system, which is obtained from the 2D SO(3) quantum Heisenberg model, on a square lattice, with nearest neighbors interaction, by taking a Gaussian random distribution of couplings centered in an antiferromagnetic coupling, $\bar J>0$ and with a width $\Delta J$. Using coherent spin states we can integrate over the random variables and map the system onto a field theory, which is a generalization of the SO(3) nonlinear sigma model with different flavors corresponding to the replicas, coupling parameter proportional to $\bar J$ and having a quartic spin interaction proportional to the disorder ($\Delta J$). After deriving the CP$^1$ version of the system, we perform a calculation of the free energy density in the limit of zero replicas, which fully includes the quantum fluctuations of the CP$^1$ fields $z_i$. We, thereby obtain the phase diagram of the system in terms of ($T, \bar J, \Delta J$). This presents an ordered antiferromagnetic (AF) phase, a paramagnetic (PM) phase and a spin-glass (SG) phase. A critical curve separating the PM and SG phases ends at a quantum critical point located between the AF and SG phases, at T=0. The Edwards-Anderson order parameter, as well as the magnetic susceptibilities are explicitly obtained in each of the three phases as a function of the three control parameters. The magnetic susceptibilities show a Curie-type behavior at high temperatures and exhibit a clear cusp, characteristic of the SG transition, at the transition line. The thermodynamic stability of the phases is investigated by a careful analysis of the Hessian matrix of the free energy. We show that all principal minors of the Hessian are positive in the limit of zero replicas, implying in particular that the SG phase is stable.Comment: To appear in Nucl. Phys B [FS], 16 pages, 6 figure

The average longitudinal air shower profile: exploring the shape information

The shape of the extensive air shower (EAS) longitudinal profile contains information about the nature of the primary cosmic ray. However, with the current detection capabilities, the assessment of this quantity in an event-by-event basis is still very challenging. In this work we show that the average longitudinal profile can be used to characterise the average behaviour of high energy cosmic rays. Using the concept of universal shower profile it is possible to describe the shape of the average profile in terms of two variables, which can be already measured by the current experiments. These variables present sensitivity to both average primary mass composition and to hadronic interaction properties in shower development. We demonstrate that the shape of the average muon production depth profile can be explored in the same way as the electromagnetic profile having a higher power of discrimination for the state of the art hadronic interaction models. The combination of the shape variables of both profiles provides a new powerful test to the existing hadronic interaction models, and may also provide important hints about multi-particle production at the highest energies.Peer Reviewe

Stable Mean Field Solution of a Short-Range Interacting SO(3) Quantum Heisenberg Spin-Glass

We present a mean-field solution for a quantum, short-range interacting, disordered, SO(3) Heisenberg spin model, in which the Gaussian distribution of couplings is centered in an AF coupling $\bar J>0$, and which, for weak disorder, can be treated as a perturbation of the pure AF Heisenberg system. The phase diagram contains, apart from a N\'eel phase at T=0, spin-glass and paramagnetic phases whose thermodynamic stability is demonstrated by an analysis of the Hessian matrix of the free-energy. The magnetic susceptibilities exhibit the typical cusp of a spin-glass transition.Comment: 4 page

Conteúdo de noradrenalina do hipotálamo e tronco-encefálico de ratos inoculados com Trypanosoma Cruzi

Noradrenaline was assayed fluorimetrically in the hypothalamus and brainstem of rats killed 20 and 32 days after inoculation with the Y strain of T. cruzi (300,000 trypomastigotes i.p.). In these animals and their normal controls the right atrial appendages were submitted to the glyoxilic acid fluorescence technique for the demonstration of noradrenergic nerves. The noradrenaline content of the brain-stem and hypothalamus of the infected animals was not significantly different from that of controls. In the atrial appendages, however, an almost complete noradrenergic denervation was observed. This result indicates that the mechanism involved in neuronal lesion in Chagas'disease discriminates between peripheral and central noradrenergic neurons.O conteúdo de noradrenalina do hipotálamo e do tronco encefálico de ratos controle e inoculados com a cepa Y (300.000 tripomastigotas, i.p.) de Trypanosoma cruzi foi medido pela técnica fluorimétrica de Anton e Sayre. Os animais foram sacrificados 20 e 32 dias depois da inoculação. Para avaliação do grau de desnervação simpática do coração dos animais infectados, a aurícula direita foi observada com microscópio de fluorescência após tratamento histoquímieo pela técnica do ácido glioxílico. O conteúdo de noradrenalina do hipotálamo e do tronco encefálico dos animais infectados não diferiu do medido nos animais controle. Contudo, um quase completo desaparecimento das fibras adrenérgicas foi observado no coração dos animais chagásicos, sugerindo que o mechanismo envolvido na lesão discrimina neurônios adrenérgicos centrais e periféricos

Dieta artificial para criação de Cosmopolites sordidus (Germ.)(Col.: Curculionidae) visando a programas de manejo integrado da praga.

A broca-do-rizoma, Cosmopolites sordidus (Germ.), é considerada a mais severa praga da bananeira, em razão dos prejuízos causados às plantas e da sua ampla distribuição geográfica. Essa praga ocorre em todas as regiões brasileiras e seus danos são causados pelas larvas que abrem galerias no rizoma e base do pseudocaule. O ataque dessa praga, além de reduzir o tamanho dos cachos comprometendo até 50 % da produção, provoca enfraquecimento das plantas, aumento na queda das bananeiras e favorece o ataque do mal-do-Panamá. Considerando a variabilidade genética existente nas populações de C. sordidus e suas implicações na seleção e avaliação de técnicas de controle de pragas, o estabelecimento de um programa de criação da broca-do-rizoma em laboratório é fundamental para o alcance de resultados promissores no manejo integrado do inseto. Este trabalho tem como objetivo determinar diferenças biológicas entre populações de C. sordidus provenientes de regiões produtoras de banana no Brasil e selecionar a(s) dieta(s) mais adequada(s) ao desenvolvimento de populações de C. sordidus em laboratório.PDF. 025

Leigh syndrome with atypical cerebellar lesions

Leigh Syndrome is a neurodegenerative disorder caused by mitochondrial dysfunction, with significant phenotypic and genetic heterogeneity. It usually presents in early life, with a severe prognosis. It can be caused by more than 75 different gene mutations, of nuclear and mitochondrial origin, involving all respiratory chain complexes, with less than 25% of Leigh syndrome having mitochondrial DNA mutations. The typical pathologic hallmarks are focal, bilateral, and symmetric lesions in the basal ganglia, thalamus, cerebellum, cerebral white matter and spinal cord gray matter, usually with T2WI and FLAIR hyperintensity. The basal ganglia and thalami frequently present with a pattern of cytotoxic edema. We present one case with clinical and analytical features consistent with Leigh Syndrome, with peculiar imaging features, showing dominant cerebellar edematous changes with unexpected petechial component suggestive of microangiopathy. To our knowledge, these features are unreported and suggest the existence of microvascular lesions. Based on the reported imaging findings, we propose that Leigh Syndrome should be added to the differential diagnosis of acute cerebellitis.info:eu-repo/semantics/publishedVersio

Bananeiras e plátanos em sistemas agroflorestais do Baixo Sul da Bahia.

As características socioeconômicas, ambientais e culturais do Baixo Sul da Bahia permitiram o desenvolvimento e a expansão de sistemas integrados de produção, com destaque para os sistemas agroflorestais. Bananeiras e plátanos são culturas agrícolas comuns na maioria dos arranjos produtivos de sistemas agroflorestais encontrados nessa região