bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance Study of All-optical Header Extractor based on SOA-MZI with Bidirectional Data Injection
Authors: Liu Huanlin , Wang YangYang , Fang Qiang , Bai Xiaotang
Published: October 2011

The performance of a all-optical header extraction scheme using semiconductor optical amplifier and Mach–Zehnder-Interferometer (SOA-MZI) with bidirectional data injection was studied at the packet rate of 80 Gb/s for ultrafast all-optical packet switching networks. Numerical analysis and simulation results showed that the contrast ratio of optical header extraction could exceed 18dB when input signal energy was as low as 0.1 pJ. In addition, the parameters of SOA-MZI and the input signal features were discussed to optimize the performance of proposed scheme.
Strain Gage Analysis for Nonlinear Pile Stiffness
Authors: Sinnreich Jon
Published: October 2011

Interpreting strain gage data from deep foundation (pile) axial load tests is usually assumed to be a simple calculation. The measured strain at any point in the test is multiplied by the computed Young’s modulus E of the pile to obtain stress. The stress is then multiplied by the cross-sectional area A to derive the load carried by the pile at the elevation of the strain gage. However, if the product of A and E (the axial pile stiffness) is nonlinear, the load-strain path must be considered and an incremental approach taken in order to approximate the true load value. Concrete cast-in-place piles may develop transverse tensile cracks, either due to soil restraint during curing or as a result of applied tensile loads. As such cracks open and close, the resultant axial pile stiffness will change significantly and abruptly, and the assumption of a constant stiffness can lead to significant error when computing loads from strain gages. This paper presents the mathematical derivation of the incremental load-strain calculation and case histories to illustrate the method.
Large-Scale Heterogeneous Representation of Sound Attributes in Rat Primary Auditory Cortex: From Unit Activity to Population Dynamics
Authors: Ogawa Takeshi , Riera Jorge , Goto Takakuni , Sumiyoshi Akira , Nonaka Hiroi , Jerbi Karim , Bertrand Olivier , Kawashima Ryuta
Published: October 2011

Recent evidence indicates the existence of pyramidal cells (PCs) and interneurons with nontrivial tuning characteristics for sound attributes in the primary auditory cortex (A1) of mammals. These neurons are functionally distributed into layers and sparsely organized at a small scale. However, their topological locations at a large scale in A1 have not yet been investigated. Furthermore, these neurons are usually classified from fine maps of attribute-dependent spiking activity, and not much attention is paid to population postsynaptic potentials related to their activity. We used extracellular recordings obtained from multiple sites in A1 of adult rats to determine neuronal codifiers for sound attributes defined by coarse representations of the population dose–response curves. We demonstrated that these codifiers, majorly involving PCs, are heterogeneously distributed along A1. Spiking activity in these neurons during stimulation was correlated to β (12–25 Hz) and low γ (25–70 Hz) postsynaptic oscillations in the infragranular layer, whereas in the supragranular layer, better correlations were found with high γ (70–170 Hz) oscillations. The time-frequency analysis of the postsynaptic potentials showed a transient broadband power increase in all layers after the stimulus onset that was followed by a sustained high γ oscillation in the supragranular layer, fluctuations in the laminar content of the low-frequency oscillations, and a global attenuation in the low-frequency powers after the stimulus offset that happened together with a long-lasting strengthening of the β oscillations. We concluded that, for rats, sounds are codified in A1 by segregated networks of specialized PCs whose postsynaptic activity impinges on the emergence of sparse/dense spiking patterns.
Distinct RolesIn Vivofor the Ubiquitin–Proteasome System and the Autophagy–Lysosomal Pathway in the Degradation of α-Synuclein
Authors: Ebrahimi-Fakhari Darius , Cantuti-Castelvetri Ippolita , Fan Zhanyun , Rockenstein Edward , Masliah Eliezer , Hyman Bradley T. , McLean Pamela J. , Unni Vivek K.
Published: October 2011

Increased intracellular levels of α-synuclein are implicated in Parkinson's disease and related disorders and may be caused by alterations in the ubiquitin–proteasome system (UPS) or the autophagy–lysosomal pathway (ALP). A critical question remains how α-synuclein is degraded by neuronsin vivo. To address this, our study uses α-synuclein transgenic mice, expressing human α-synuclein or α-synuclein-eGFP under the (h)PDGF-β promoter, in combination within vivopharmacologic and multiphoton imaging strategies to systematically test degradation pathways in the living mouse brain. We demonstrate that the UPS is the main degradation pathway for α-synuclein under normal conditionsin vivowhile with increased α-synuclein burden the ALP is recruited. Moreover, we report alterations of the UPS in α-synuclein transgenic mice and age dependence to the role of the UPS in α-synuclein degradation. In addition, we provide evidence that the UPS and ALP might be functionally connected such that impairment of one can upregulate the other. These results provide a novel link between the UPS, the ALP, and α-synuclein pathology and may have important implications for future therapeutics targeting degradation pathways.
A Signaling Mechanism Coupling Netrin-1/Deleted in Colorectal Cancer Chemoattraction to SNARE-Mediated Exocytosis in Axonal Growth Cones
Authors: Cotrufo Tiziana , Pérez-Brangulí Francesc , Muhaisen Ashraf , Ros Oriol , Andrés Rosa , Baeriswyl Thomas , Fuschini Giulia , Tarrago Teresa , Pascual Marta , Ureña Jesús , Blasi Joan , Giralt Ernest , Stoeckli Esther T. , Soriano Eduardo
Published: October 2011

Directed cell migration and axonal guidance are essential steps in neural development. Both processes are controlled by specific guidance cues that activate the signaling cascades that ultimately control cytoskeletal dynamics. Another essential step in migration and axonal guidance is the regulation of plasmalemma turnover and exocytosis in leading edges and growth cones. However, the cross talk mechanisms linking guidance receptors and membrane exocytosis are not understood. Netrin-1 is a chemoattractive cue required for the formation of commissural pathways. Here, we show that the Netrin-1 receptor deleted in colorectal cancer (DCC) forms a protein complex with the t-SNARE (target SNARE) protein Syntaxin-1 (Sytx1). This interaction is Netrin-1 dependent bothin vitroandin vivo, and requires specific Sytx1 and DCC domains. Blockade of Sytx1 function by using botulinum toxins abolished Netrin-1-dependent chemoattraction of axons in mouse neuronal cultures. Similar loss-of-function experiments in the chicken spinal cordin vivousing dominant-negative Sytx1 constructs or RNAi led to defects in commissural axon pathfinding reminiscent to those described in Netrin-1 and DCC loss-of-function models. We also show that Netrin-1 elicits exocytosis at growth cones in a Sytx1-dependent manner. Moreover, we demonstrate that the Sytx1/DCC complex associates with the v-SNARE (vesicle SNARE) tetanus neurotoxin-insensitive vesicle-associated membrane protein (TI-VAMP) and that knockdown of TI-VAMP in the commissural pathway in the spinal cord results in aberrant axonal guidance phenotypes. Our data provide evidence of a new signaling mechanism that couples chemotropic Netrin-1/DCC axonal guidance and Sytx1/TI-VAMP SNARE proteins regulating membrane turnover and exocytosis.
Resonating with Others: The Effects of Self-Construal Type on Motor Cortical Output
Authors: Obhi Sukhvinder S. , Hogeveen Jeremy , Pascual-Leone Alvaro
Published: October 2011

“Self-construal” refers to how individuals view and make meaning of the self, and at least two subtypes have been identified. Interdependent self-construal is a view of the self that includes relationships with others, and independent self-construal is a view of the self that does not include relations with others. It has been suggested that priming these two types of self-construal affects the cognitive processing style that an individual adopts, especially with regard to context sensitivity. Specifically, an interdependent self-construal is thought to promote attention to others and social context to a greater degree than an independent self-construal. To investigate this assertion, we elicited motor-evoked potentials with transcranial magnetic stimulation during an action observation task in which human participants were presented with either interdependent or independent self-construal prime words. Priming interdependent self-construal increased motor cortical output whereas priming independent self-construal did not, compared with a no-priming baseline condition. These effects, likely mediated by changes in the mirror system, essentially tune the individual to, or shield the individual from, social input. Interestingly, the pattern of these self-construal-induced changes in the motor system corroborates with previously observed self-construal effects on overt behavioral mimicry in social settings, and as such, our results provide strong evidence that motor resonance likely mediates nonconscious mimicry in social settings. Finally, these self-construal effects may lead to the development of interventions for disorders of deficient or excessive social influence, like certain autism spectrum and compulsive imitative disorders.
Synaptic Action of the Olivocerebellar System on Cerebellar Nuclear Spike Activity
Authors: Blenkinsop Timothy A. , Lang Eric J.
Published: October 2011

Cerebellar output is necessary for the ideal implementation of many nervous system functions, particularly motor coordination. A key step toward understanding the generation of this output is characterizing the factors that shape the activity of the cerebellar nuclei (CN). There are four major sources of synaptic input that modulate CN activity; collaterals of climbing and mossy fibers are two, and the remaining two are provided by Purkinje cell (PC) axons in the form of simple spikes (SSs) and complex spikes (CSs). Most hypotheses of cerebellar function focus on SSs as the primary determinant of CN activity. However, it is likely that CSs also cause significant direct effects on CN activity, something that is rarely considered. To explore this possibility, we recorded from synaptically connected PC–CN neuron cell pairs in rats. Cross-correlograms of CS and CN activity from such recordings demonstrate that spontaneous CSs have a strong inhibitory effect on CN activity, apparently sufficient, in some cases, to trigger changes in the intrinsic excitability of the CN neuron that long outlast the underlying CS-mediated GABAergic IPSP. Furthermore, many CS–CN correlograms show an initial excitatory response, demonstrating the ability of climbing fiber collaterals to significantly excite CN neurons. A substantial fraction (24%) of correlograms displayed an excitation–inhibition sequence, providing evidence that a CN neuron often receives collaterals from the same olivocerebellar axons as innervate the PCs projecting to it. Thus, excitation followed by inhibition appears to be a hard-wired response pattern of many CN neurons to olivocerebellar activity.
Emotional Facial Expressions Modulate Pain-Induced Beta and Gamma Oscillations in Sensorimotor Cortex
Authors: Senkowski Daniel , Kautz Janine , Hauck Michael , Zimmermann Roger , Engel Andreas K.
Published: October 2011

Painful events in our environment are often accompanied by stimuli from other sensory modalities. These stimuli may influence the perception and processing of acute pain, in particular when they comprise emotional cues, like facial expressions of people surrounding us. In this whole-head magnetoencephalography (MEG) study, we examined the neuronal mechanisms underlying the influence of emotional (fearful, angry, or happy) compared to neutral facial expressions on the processing of pain in humans. Independent of their valence, subjective pain ratings for intracutaneous inputs were higher when pain stimuli were presented together with emotional facial expressions than when they were presented with a neutral facial expression. Source reconstruction using linear beamforming revealed pain-induced early (70–270 ms) oscillatory beta-band activity (BBA; 15–25 Hz) and gamma-band activity (GBA; 60–80 Hz) in the sensorimotor cortex. The presentation of faces with emotional expressions compared to faces with neutral expressions led to a stronger bilateral suppression of the pain-induced BBA, possibly reflecting enhanced response readiness of the sensorimotor system. Moreover, pain-induced GBA in the sensorimotor cortex was larger for faces expressing fear than for faces expressing anger, which might reflect the facilitation of avoidance-motivated behavior triggered by the concurrent presentation of faces with fearful expressions and painful stimuli. Thus, the presence of emotional cues, like facial expressions from people surrounding us, while receiving acute pain may facilitate neuronal processes involved in the preparation and execution of adequate protective motor responses.
Simulation physiologischer Regelkreise mit der objektorientierten Modellbibliothek “HumanLib”
Authors: Brunberg Anja , Spillner Jan , Autschbach Rüdiger , Abel Dirk
Published: October 2011

Die “HumanLib” ist eine objektorientiert aufgebaute Modellbibliothek bestehend aus Komponenten des Herz-Kreislauf-Systems sowie körpereigenen Regelkreisen. Im Beitrag werden Aufbau und Modellierungsmethodik beschrieben. Anhand zweier Testszenarien werden Simulationsdaten mit Messdaten aus einem in vivo Versuch am Kalb sowie physiologischen Normalwerten verglichen.
Gelenkwinkelregelung durch Elektrostimulation eines antagonistischen Muskelpaares
Authors: Klauer Christian , Schauer Thomas , Raisch Jörg
Published: October 2011

Dieser Beitrag beschreibt einen neuen Ansatz zur kaskadierten Positionsregelung menschlicher Extremitäten unter Elektrostimulation, welcher auch eine Rückführung der Beschleunigung in Form eines Störgrößenbeobachters verwendet. Bei der Stimulation eines antagonistischen Muskelpaares kann dieser Regelungsansatz unerwünschte Effekte, die durch eine nicht exakt bekannte Totzone in der muskulären Aktivierung hervorgerufen werden, deutlich reduzieren. Der Reglerentwurf basiert auf einem stark vereinfachten neuro-muskulären Modell, das mit geringem Aufwand an den Probanden angepasst werden kann.
Understanding anisotropic microstrain broadening in Rietveld refinement
Authors: Leineweber Andreas
Published: October 2011

Anisotropic, i.e.
hkl-dependent microstrain broadening of Bragg peaks as observed in powder-diffraction measurements often obstructs finding a good description of the peak profiles during Rietveld refinement. This review describes strategies to model this type of structural line broadening. Emphasis is put, further, on the possible physical background of the refined width parameters in terms of compositional, thermal and elastic microstrain. Methods are described to extract thus quantitative microstructural information. Moreover, it is shown how the anisotropy of the microstrain broadening can reveal the anisotropy of intrinsic properties of the solid, which may otherwise be difficult to determine, e.g. compositional lattice-parameter changes or elastic compliance.
Solving a Meiotic LEGO® Puzzle: Transverse Filaments and the Assembly of the Synaptonemal Complex in Caenorhabditis elegans
Authors: Hawley R Scott
Published: October 2011

The structure of the meiosis-specific synaptonemal complex, which is perhaps the central visible characteristic of meiotic prophase, has been a matter of intense interest for decades. Although a general picture of the interactions between the transverse filament proteins that create this structure has emerged from studies in a variety of organisms, a recent analysis of synaptonemal complex structure in Caenorhabditis elegans by Schild-Prüfert et al. (2011) has provided the clearest picture of the structure of the architecture of a synaptonemal complex to date. Although the transverse filaments of the worm synaptonemal complex are assembled differently then those observed in yeast, mammalian, and Drosophila synaptonemal complexes, a comparison of the four assemblies shows that achieving the overall basic structure of the synaptonemal complex is far more crucial than conserving the structures of the individual transverse filaments.
Simulations of Gallium Antimonide (GaSb) p-B-n Thermophotovoltaic Cells
Authors: DeMeo Dante F. , Vandervelde Thomas E.
Published: October 2011

The focus of this paper is the characterization of novel thermophotovoltaic (TPV) cell designs which employ a monovalent barrier layer in the p-n junction. The use of a barrier layer enables these cells to operate at longer wavelengths, higher efficiencies, and higher operating temperatures. Initial designs have been made using gallium antimonide (GaSb), which is one of the more common TPV materials. Simulations were performed using Sentaurus by Synopsys to determine barrier materials as well as to optimize the cell. The p-B-n cell was then compared to a simple p-n junction. The simulations show that a p-B-n cell outperforms a typical p-n junction. Additionally, we expect to see increased performance differentials from this device structure when moving to longer wavelength devices.
Dysprosium-Containing Nanocrystals for Thermal Neutron Detection
Authors: Rivera Antonio C. , Glazener Natasha N. , Cook Nathaniel C. , Withers Nathan J. , Plumley John B. , Akins Brian A. , Carpenter Ken , Smolyakov Gennady A. , Busch Robert D. , Osiński Marek
Published: October 2011

We propose a novel concept of optical detection of thermal neutrons in a passive device that exploits transmutation of Dy-164, a dominant, naturally occurring isotope of dysprosium, into a stable isotope of either holmium Ho-165 or erbium Er-166. Combination of the high thermal neutron capture cross section of ~2,650 barns and transmutation into two other lanthanides makes Dy-164 a very attractive alternative to traditional methods of neutron detection that will be completely insensitive to gamma irradiation, thus reducing greatly the likelihood of false alarms. The optically enabled neutron detection relies on significant differences in optical properties of Dy, Ho, and Er that are not sensitive to a particular isotope, but change considerably from one element to another. While the concept applies equally well to bulk materials and to nanocrystals, nanocrystalline approach is much more attractive due to its significantly lower cost, relative ease of colloidal synthesis of high quality nanocrystals (NCs), and superior optical and mechanical properties of NCs compared to their bulk counterparts. We report on colloidal synthesis of DyF3 NCs, both doped and undoped with Ho and co-doped with Ce and Eu to enhance their optical properties. We also report on DyF3:10%Ce and DyF3:10%Eu NCs irradiated with thermal neutrons from a Cf-252 source and their optical characterization.
Discriminação de fitofisionomias de floresta de várzea a partir do algoritmo Iterated Conditional Modes aplicado aos dados SAR/R99 (QUAD-POL/Banda L)
Authors: Nunes Gustavo Manzon , Souza Filho Carlos Roberto de , Ferreira Laerte Guimarães
Published: October 2011

Utilizando-se dados do sensor aerotransportado SAR R99, adquiridos na banda L (1,28 GHz) em amplitude e com quatro polarizações (HH, VV, HV e VH), avaliou-se a distinção de fitofisionomias de floresta de várzea existentes nas Reservas de Desenvolvimento Sustentável Amanã e Mamirauá e áreas adjacentes, com a aplicação do algoritmo Iterated Conditional Modes (ICM) de classificação polarimétrica pontual/contextual. Os resultados mostraram que o uso das distribuições multivariadas em amplitude, conjuntamente com uma banda de textura, produziu classificações de qualidade superior àquelas obtidas com dados polarimétricos uni/bivariados. Esta abordagem permitiu a obtenção de um índice Kappa de 0,8963, discriminando as três classes vegetacionais de interesse, comprovando assim o potencial dos dados do SAR R99 e do algoritmo ICM no mapeamento de florestas de várzea da Amazônia.
Influência do hábitat na estrutura da comunidade de macroinvertebrados aquáticos associados às raízes de Eichhornia crassipes na região do Lago Catalão, Amazonas, Brasil
Authors: Lopes Aline , Paula Joana D'Arc de , Mardegan Silvia Fernanda , Hamada Neusa , Piedade Maria Teresa Fernandez
Published: October 2011

Por possuírem ciclos de vida curtos, os macroinvertebrados aquáticos podem responder rapidamente às modificações ambientais, alterando a estrutura das suas populações e comunidades. O objetivo deste estudo foi determinar se há relação entre a composição de macroinvertebrados aquáticos associados a bancos de Eichhornia crassipes o gradiente de condutividade elétrica da água e a biomassa das raízes destes bancos. No pico da cheia de 2005, 21 bancos de macrófitas aquáticas flutuantes dominados por E. crassipes foram amostrados no rio Negro (baixa condutividade < 30 µS cm-1), na confluência entre os rios Negro e Solimões (média condutividade > 30 µS cm-1 e < 50 µS cm-1), e no rio Solimões (alta condutividade > 50 µS cm-1). Foram encontrados 1707 macroinvertebrados aquáticos, distribuídos em 14 ordens e 35 famílias. A abundância de invertebrados aquáticos foi maior em bancos na confluência das águas. O aumento da biomassa das raízes de E. crassipes levou a um aumento da abundância e da riqueza de famílias de macroinvertebrados. A abundância dos coletores-catadores, coletores-filtradores e raspadores variou com o tipo de água, e apenas a abundância dos coletores-catadores e coletores-filtradores variou em função da biomassa das raízes. A riqueza de famílias dos raspadores variou em função do tipo de água. A organização da comunidade depende do gradiente de biomassa de raízes, indicando a importância da estrutura do hábitat para o estabelecimento dos macroinvertebrados.
Mites (Arachnida, Acari) on Citrus sinensis L. Osbeck orange trees in the state of Amazonas, Northern Brazil
Authors: Bobot Teiamar da Encarnação , Franklin Elizabeth , Navia Denise , Gasnier Thierry Ray Jehlen , Lofego Antonio Carlos , Oliveira Byatryz Mortágua de
Published: October 2011

Despite the importance of citriculture in Brazil, very little is known about mite populations in citrus crops in the Northern Region. In the municipality of Manaus, 12 sprayed sweet orange orchards were surveyed every two weeks during seven months to record mite species amount, and to describe the abundance and distribution of the most important species. The size and age of the orchards varied from 3,360 to 88,080 m² and seven to 25 years, respectively. In the fourteen sampling period, leaves, twigs and fruits were collected from 12 trees, one per orchard. In total, 3,360 leaves, 672 twigs and 1,344 fruits were sampled from 168 trees. Mites were manually extracted from the fruits, and by the washing method on leaves and twigs. We identified pests with the potential to cause economic loss. Fourteen species of phytophagous and mycophagous mites from Eriophyidae, Tarsonemidae, Tenuipalpidae, and Tetranychidae were recorded. Brevipalpus phoenicis (Geijskes 1939) and Phyllocoptruta oleivora (Ashm., 1879), the two commonest phytophagous mites in other Brazilian regions were dominant, showing that local orchards are susceptible to their infestation. Eleven predatory mites were recorded, comprising 10% of the mite population, belonging to Phytoseiidae and Ascidae. Phytoseiidae was the richest family, with ten species. The results are discussed in relation to the temporal variation aspects and habitat use of the most important species. Long-term research encompassing chemical applications followed by evaluations of the mite community are necessary for a better management of the orchards, taking into consideration the seasonal phenology of key pests.
Does nitrogen availability have greater control over the formation of tropical heath forests than water stress?A hypothesis based on nitrogen isotope ratios
Authors: Brearley Francis Q , Fine Paul V. A , Perreijn Kristel
Published: October 2011

Global scale analyses of soil and foliage δ15N have found positive relationships between δ15N and ecosystem N loss (suggesting an open N cycle) and a negative relationship between δ15N and water availability. We show here that soils and leaves from tropical heath forests are depleted in 15N relative to 'typical' forests suggesting that they have a tight N cycle and are therefore limited by N rather than by, often suggested, water availability.
Regeneração de uma população natural de Araucaria angustifolia (Araucariaceae)
Authors: Paludo Giovani Festa , Mantovani Adelar , Reis Maurício Sedrez dos
Published: October 2011

Estudos têm indicado baixa capacidade de regeneração em Araucaria angustifolia (Bertol.) Kuntze, baseados principalmente no baixo número de indivíduos regenerantes, não existindo estudos da dinâmica da regeneração natural. Dessa forma, o objetivo deste trabalho foi estudar a dinâmica da regeneração de plantas de uma população natural conservada de A. angustifolia sob uma floresta desenvolvida. Em uma parcela permanente de 5,1 ha, na Reserva Genética Florestal de Caçador (SC), foram avaliados, em três anos consecutivos, os indivíduos regenerantes (< 5 m de altura) e discutidos os principais fatores responsáveis pela estrutura encontrada, sendo o padrão espacial analisado com a Função K, de Ripley. Foi encontrada variação no número de ingressantes entre os anos avaliados, bem como nos indivíduos mortos. O estágio crítico para a regeneração da espécie se mostrou logo nos primeiros anos de desenvolvimento até os 0,5 m de altura. A agregação predominou nos indivíduos ingressantes e na regeneração natural como um todo. Mas como a espécie é longeva, ela pode manter baixo número de indivíduos regenerantes na população e, mesmo assim, ter sucesso na regeneração.
Efeito de borda na diversidade, composição e estrutura da comunidade arbórea em uma floresta estacional decidual no Brasil Central
Authors: Sampaio Alexandre Bonesso , Scariot Aldicir
Published: October 2011

O efeito da distância da borda na estrutura, composição e diversidade da comunidade de árvores, considerando todos os tamanhos de indivíduos, foi estudado em um fragmento bem preservado de Floresta Estacional Decidual no Nordeste do Estado de Goiás, Brasil. Parcelas foram sistematicamente estabelecidas em seis distâncias (0, 40, 80, 160, 280 e 400 m) da borda, ao longo de 10 transecções ortogonais na borda floresta-pastagem. Foram amostrados 602 indivíduos adultos/ha, 8.927 indivíduos juvenis/ha e 54.167 plântulas/ha distribuídas em 58 espécies. Embora a composição de plântulas e adultos tenha variado significativamente ao longo do gradiente floresta-pastagem, a variação explicada pela distância da borda foi abaixo de 4%. Entre as variáveis de estrutura da comunidade e os índices de diversidade testados houve variação significativa apenas na diversidade de plântulas e na altura de adultos entre as distâncias da borda floresta-pastagem. O fragmento de floresta estacional apresentou apenas tênue efeito de borda, considerando-se os parâmetros de comunidade avaliados. Essa conclusão contrasta com resultados encontrados em florestas tropicais úmidas, os quais indicam diferenças abruptas entre a comunidade de árvores da borda e as do interior de fragmentos florestais.
Risk factors associated with the frequency of antibodies against Babesia bovis and Babesia bigemina in cattle in southern Mozambique
Authors: Tembue António A.M. , Silva Fábio J.M. , Silva Jenevaldo B. , Santos Tiago M. , Santos Huarrisson A. , Soares Cleber O. , Fonseca Adivaldo H.
Published: October 2011

The study aimed to evaluate the risk factors associated with the frequency of IgG antibodies against Babesia bovis and B. bigemina in cattle in southern Mozambique. Eight hundred and nine serum samples were collected from cattle in three provinces namely Maputo, Gaza and Inhambane, and tested by indirect enzyme-linked immunosorbent assay (i-ELISA) to assess the humoral immune response towards B. bovis and B. bigemina. The chi-square test at 5% significance was used to determine whether there was an association between gender, age and geographic origin of seropositive animals. The overall prevalence was 78.8% (548/695) for B. bovis and 76.0% (528/695) for B. bigemina. The origin of the animals showed a significant association (p<0.05) with seropositivity to both agents, while gender and age was not associated (p>0.05). Maputo province had the highest rate of positive animals, with 93.7% (118/126) for B. bovis and 97.6% (123/126) for B. bigemina. In Gaza province 77.3% (321/415) of the animals were positive for B. bovis and 67.5% (280/415) for B. bigemina, while in the province of Inhambane the levels of seropositivity were 70.8% (109/154) and 81.2% (125/154) for B. bovis and B. bigemina respectively. In the present study, the frequency of cattle positive for B. bovis and B. bigemina was shown to increase among older age groups, suggesting that infection and re-infection persisted even after the primary infection. Thus, this region is considered to be in a state of enzootic stability with regards to B. bovis and B. bigemina.
Perfil de resistência a antimicrobianos de Staphylococcus spp. isolados de frangos de corte e poedeiras comerciais no estado de Pernambuco
Authors: Barros Mércia R. , Costa Mateus M. da , França Chirles A. de , Saukas Tomoe N. , Silva Leonildo B.G. da , Silva Vanessa Anny S. , Cavalcante Raíssa V. , Mota Rinaldo A.
Published: October 2011

Este estudo foi realizado com o objetivo de pesquisar Staphylococcus spp. de frangos de corte sadios e frangos de corte e poedeiras comerciais que apresentassem sinais clínicos respiratórios. Foram colhidos swabs dos seios infra-orbitários de 55 frangos de corte sadios, 35 com sinais respiratórios, e 30 poedeiras comerciais também com sinais respiratórios. Cada amostra foi composta por um "pool" de cinco aves, totalizando 24 amostras coletadas de 24 granjas comerciais. Para o isolamento foi utilizado o exame bacteriológico, com posterior avaliação das características morfológicas, tintoriais e bioquímica para determinação da espécie. Verificou-se a produção de hemólise, formação de biofilme em ágar Vermelho Congo (ACR), detecção do gene mecA pela PCR e avaliação da suscetibilidade a 13 drogas antimicrobianas. Das 24 amostras processadas, foram isolados 16 Staphylococcus, cinco isolados foram coagulase-positiva (SCP) e 11 coagulase-negativa (SCN), e nos testes de hemólise e formação de biofilme, três isolados apresentaram-se hemolíticos e seis foram positivos, respectivamente. Na avaliação por meio da PCR, para detecção do gene mecA todos os isolados apresentaram resultados negativo. Observaram-se que 15 isolados foram resistentes a cinco ou mais antibióticos, e que as drogas associadas apresentaram melhor perfil de sensibilidade. A resistência a antimicrobianos e cepas produtoras de biofilme podem interferir na resposta terapêutica de aves que apresentam sinais clínicos.
Curva de anticorpos pós-vacinais em ovinos imunizados com uma ou duas doses de bacterina oleosa anti-leptospirose, produzida com a sorovariedade Hardjo, tipo Hardjoprajitno, estirpe Norma, isolada no Brasil
Authors: Herrmann Geder Paulo , Rodrigues Rogério Oliveira , Vidal Carlos Eugênio Soto , Machado Gustavo , Moreira Élvio Carlos , Leite Rômulo Cerqueira
Published: October 2011

Foi comparado o nível de anticorpos de ovelhas imunizadas com uma ou duas doses de bacterina oleosa produzida com a sorovariedade Hardjo, tipo Hardjoprajitno, estirpe Norma, isolada da urina de bovino no Brasil. Culturas de 2x10(8) leptospiras/mL foram inativadas com formalina a 0,3%, à concentração final e emulsionada em óleo Emulsigen® 12%. A dose da vacina foi padronizada para a concentração de 1x10(8) leptospiras/mL. Quarenta ovinos adultos, da raça Santa Inês, de um rebanho livre de leptospirose por exames clínicos e sorológicos durante um ano foram escolhidos para o experimento. O grupo A (n=15) recebeu duas doses de 3,0mL da vacina por via subcutânea, com intervalo de 30 dias. O grupo B (n=15) recebeu dose única de 3,0mL, via subcutânea e o grupo C (controle) recebeu uma dose subcutânea de 3,0mL de solução 0,85% de cloreto de sódio. Os títulos de anticorpos pós-vacinação foram mensurados pelo teste de soroaglutinação microscópica (SAM) e um teste imunoenzimático (ELISA) a cada 30 dias durante 120 dias. Os títulos dos grupos A e B na primeira colheita variaram de 80 a 160. No grupo A, após a segunda dose, os títulos aumentaram duas a quatro vezes, até 3.200, enquanto no grupo B os títulos de aglutininas foram menores que 160 e diminuíram uma a duas vezes após 60 dias da vacinação. Utilizando-se dose única, os anticorpos persistiram por somente 30 dias e, com duas doses, com 30 dias de intervalo, os anticorpos foram detectáveis por 60 dias por meio do teste de SAM e 120 dias no teste de ELISA. Assim, o teste de SAM detectou títulos de IgM vacinal somente por 60 dias, enquanto o teste de ELISA foi capaz de detectar anticorpos durante os 120 dias. No grupo controle negativo, ocorreram no ELISA reações inespecíficas de títulos até 80, porém no SAM os títulos dos mesmos animais se mantiveram em zero. O teste de ELISA pode ser utilizado para medir anticorpos vacinais para a sorovariedade Hardjo, tipo Hardjoprajitno, estirpe Norma em ovinos.
Intoxicação espontânea por Senna occidentalis em javalis (Sus scrofa ferus) no estado de Goiás
Authors: Sant'Ana Fabiano J.F. de , Garcia Edismair C. , Rabelo Rogério E. , Ferreira Júnior Cleomar da S. , Freitas Neto Argemiro P. , Verdejo Ana C.F.
Published: October 2011

Descreve-se um surto de intoxicação por Senna occidentalis em javalis no Estado de Goiás. De um rebanho de 80 javalis, 15 adoeceram e um morreu. Os sinais clínicos observados foram apatia, prostração, ataxia, tremores musculares, incoordenação, relutância em mover-se, decúbito esternal ou lateral, paresia e paralisia espástica, principalmente dos membros pélvicos. As principais alterações macroscópicas consistiam de palidez moderada a acentuada da musculatura esquelética dos membros pélvicos e torácicos e no lombo, especialmente nos músculos da coxa. Microscopicamente, observou-se degeneração e necrose flocular, multifocal, leve a moderada, monofásica, com fragmentação de fibras na musculatura esquelética. Nos cortes transversais, havia fibras musculares tumefeitas e hipereosinofílicas. Adicionalmente, havia degeneração microvacuolar hepatocelular difusa, leve a moderada. A atividade sérica da CK estava acentuadamente elevada em dois javalis avaliados e da TGO aumentou em um javali afetado.
Hypomethylation of tumor suppressor genes in odontogenic myxoma
Authors: Moreira Paula Rocha , Cardoso Fabiano Pereira , Brito João Artur Ricieri , Batista Aline Carvalho , Gomes Carolina Cavaliéri , Gomez Ricardo Santiago
Published: October 2011

Odontogenic myxoma (OM) is an ectomesenchymal benign odontogenic tumor characterized by spindle or stellate-shaped cells embedded in an abundant myxoid or mucoid extracellular matrix. DNA methylation is characterized by the addition of methyl groups in cytosines within CpG islands in the promoter gene. DNA methylation can decrease the expression of tumor suppressor genes and contribute to the development of neoplastic lesions. The aim of study was to evaluate the methylation pattern of the tumor suppressor genes P16 (CDKN2A), P21 (CDKN1A), P27 (CDKN1B), P53 (TP53) and RB1 in OM and dental pulp. Methylation was evaluated using methylation-specific polymerase chain reaction (PCR). The transcription was studied in some cases by using reverse transcription quantitative PCR. A higher frequency of unmethylated P27, P53, and RB1 samples was observed in the OM when compared with the dental pulp. OM expressed mRNA of all the genes evaluated. Considering all the samples together, the expression of Rb was higher in the unmethylated samples compared with the partially methylated samples. This investigation revealed hypomethylation of the genes P27, P53, and RB1 in OM. In addition, methylation of tumor suppressor genes was found to be an usual event in normal dental pulp.
Ligature of external carotid artery as an optional technique in a patient with von Willebrand disease
Authors: Faverani Leonardo Perez , Gaetti-Jardim Ellen Cristina , Ramalho-Ferreira Gabriel , Gulinelli Jessica Lemos , Queiroz Thallita Pereira , Garcia Júnior Idelmo Rangel
Published: October 2011

The von Willebrand disease (vWD) is a hereditary coagulopathy. There is no gender predilection. Clinically characterized by mucocutaneous bleeding, especially nose bleeding, menorrhagia and bleeding after trauma. This article reports a case of a 52-year-old Caucasian male patient with vWD, who presented with extensive bleeding in the tongue after a lacerating injury caused by accidental biting, and describes some clinical, pathological and treatment aspects of vWD. After repeated attempts to suture the wound and replace clotting factors, a decision was made to perform the ligature of the external carotid artery ipsilateral to the injury. There was favorable resolution of the case, with a good aspect of the scar 2 months after ligation. This case reinforces that it is extremely important to make a thorough review of medical history of all patients, searching for possible bleeding disorders or previous family history.
Percursos da constituição de uma política brasileira de educação especial inclusiva
Authors: Kassar Mônica de Carvalho Magalhães
Published: October 2011

Este artigo propõe-se a apresentar análises de alguns elementos que contribuem para a constituição da Educação Especial brasileira como uma política pública, dando especial foco à formulação do que tem sido denominada de política de educação especial na perspectiva inclusiva ou educação inclusiva. Para tanto, o texto é construído a partir da configuração de dois aspectos distintos, mas intimamente interligados. O primeiro refere-se ao papel do Governo brasileiro na história da educação destinada às pessoas com deficiências no Brasil. O segundo diz respeito às relações entre as políticas nacionais no campo da Educação e os acordos e compromissos internacionais. Conclui ressaltando a importância dos diferentes setores da sociedade nos embates atuais para a formulação de uma política de educação brasileira, que incorpore, de fato, toda a população.
Construção e validação da Escala de Avaliação da Mediação de Mães de Crianças Pequenas
Authors: Vectore Celia , Alvarenga Vanessa Cristina , Gomide Junior Sinésio
Published: October 2011

O estudo objetivou a construção e validação de uma escala de avaliação de comportamentos mediacionais, observados na interação de mães com seus filhos pequenos (até três anos de idade). Para tanto, foram arrolados 88 itens, oriundos de estudos prévios realizados por um dos autores do presente estudo, sendo submetidos à apreciação de dois juízes, com concordância em 75 dos itens avaliados; os itens foram aglutinados e a escala foi composta por 30 itens. A aplicação consistiu na observação dos comportamentos mediacionais, numa amostra de 300 mães, em momentos de interação com seus filhos. Após a aplicação, foi realizada a análise fatorial dos dados, sendo identificado apenas um fator, composto por 29 itens, resultando na Escala de Avaliação da Mediação de Mães de Crianças Pequenas, que pode ser utilizada em diagnósticos iniciais visando conhecer a qualidade da mediação ofertada pela mãe ao(à) seu(sua) filho(a) pequeno(a).
Representações sobre a Aids na velhice por coordenadoras de grupos da terceira idade
Authors: Saldanha Ana Alayde de Werba , Felix Shenia Maria Felício , Araújo Ludgleydson Fernandes de
Published: October 2011

O presente trabalho buscou apreender as representações das coordenadoras dos grupos de convivência de idosos sobre Aids na velhice. Participaram da pesquisa 20 coordenadoras do Programa de Atenção ao Idoso da Prefeitura Municipal de João Pessoa-PB, com idade variando de 38 a 72 anos. Para a coleta dos dados foi utilizado um questionário sociodemográfico e a técnica de Associação Livre de Palavra, a partir de três estímulos indutores: Aids na terceira idade, prevenção e vulnerabilidade. Emergiram as seguintes representações: as coordenadoras mais jovens associam a Aids à necessidade de cuidado, e a prevenção, ao uso de camisinha. A vulnerabilidade é associada a um fenômeno relativo a todos. Para as de maior idade, as representações estão associadas a sofrimento e a grupo de risco. O desenvolvimento de práticas educativas nos grupos constitui espaços de transformação para intervenções preventivas quanto ao HIV/Aids.
Avaliação do grau de inteligibilidade de fala de crianças com desvio fonológico: implicações nas habilidades sociais
Authors: Carlino Fabiana Cristina , Prette Almir Del , Abramides Dagma Venturini Marques
Published: October 2011

OBJETIVO: analisar a relação entre o grau de inteligibilidade de fala e as habilidades sociais de comunicação em crianças com diagnóstico de desvio fonológico. MÉTODO:participaram deste estudo 10 crianças, diagnosticadas com desvio fonológico, com idade cronológica média de 7,28 anos, sendo três do gênero feminino e sete do masculino, que realizavam terapia de linguagem duas vezes por semana em uma clínica escola de uma cidade de médio porte do estado de São Paulo. As crianças foram submetidas à avaliação da fonologia por meio do instrumento ABFW, sendo que a gravidade do desvio fonológico foi baseada no cálculo do Percentual de Consoantes Corretas (PCC). E em seguida foram filmadas em situações estruturas de interação de maneira tal a obter uma amostra de fala espontânea, para caracterizar o grau de inteligibilidade de fala (GIF), além de observar presença ou ausência dos componentes das habilidades sociais de comunicação (HSC). Para analisar a relação entre GIF e HSC foi utilizado o coeficiente de Spearman. RESULTADOS:foi possível caracterizar as classes de HSC que encontram-se deficitárias em crianças diagnosticas com desvio fonológico, além de verificar uma relação significante e positiva entre o GIF e o HSC, mostrando que quanto maior o GIF maior a dificuldades nas HSC. CONCLUSÃO: o estudo verificou a relação entre GIF e HSC, além de identificar as classes de HSC que encontram-se deficitárias em crianças com diagnóstico de desvio fonológico, favorecendo a elaboração de instrumentos para avaliação e intervenção, permitindo assim, um melhor planejamento para cada caso.
Dos saberes para ensinar aos saberes didatizados: uma análise da concepção de sequência didática segundo o isd e sua reconcepção na revista Nova Escola
Authors: Anjos-Santos Lucas Moreira dos , Lanferdini Priscila A. F. , Cristovão Vera Lúcia Lopes
Published: October 2011

Considerando a abrangência nacional de uma das maiores revistas especializadas em educação do Brasil e seu possível papel nas representações construídas por professores a partir dos conteúdos por ela veiculados, este artigo tem como objetivo analisar o conceito de sequência didática segundo o ISD e sua transposição didática pela revista Nova Escola. Para análise, partimos dos conceitos defendidos pela didática de línguas de Genebra da linha Interacionista Sociodiscursiva (ISD) (SCHNEUWLY; DOLZ, 2004) e sua (re)interpretação no quadro de didáticas de línguas estrangeiras no Brasil (CRISTOVÃO 2005, 2007, 2009; PETRECHE, 2008; BEATO-CANATO, 2009). Os resultados revelam divergências entre o conceito de SD defendido pelo ISD e as SDs publicadas pela Revista.
Epilithic community development on artificial reefs deployed along a cross-shelf environmental gradient off Paraná state, southern Brazil
Authors: Brandini Frederico , Silva Ariel Scheffer da
Published: October 2011

Concrete modules were deployed on the bottom of the 11, 18 and 30 meters isobaths along a cross-shelf hydrographic gradient off Paraná State, Southern Brazil, with the purpose of studying the colonization of sessile epilithic macroinvertebrates on artificial surfaces. After one year of submersion a total of 63 species of epilithic organisms were identified, dominated by Ostrea puelchana, Chthamalus bisinuatus, Balanus cf spongicola, Astrangia cf rathbuni, Didemnum spp, poryphers and bryozoans. Diversity index and percent cover at reef stations placed at 11, 18 and 30 meters isobaths were respectively 2.28 and 66.7%, 2.79 and 96.6% and 1.66 and 77.4%. Differences of general community structure among the three assemblages were not clearly related to the general environmental conditions at the bottom layers near the reef stations. Turbidity and larval abundance are discussed as important factors affecting colonization processes. Results indicate that depths between 15-20 meters are more suitable for the implementation of large scale artificial reef systems in the inner shelf off Paraná and, possibly, throughout the inner shelves off southern Brazil with similar hydrographic conditions.
Colonization and community development of fish assemblages associated with estuarine artificial reefs
Authors: Folpp Heath , Lowry Michael , Gregson Marcus , Suthers Iain M.
Published: October 2011

Despite the long history of the development of artificial structures in NSW estuaries there are no studies that provide any comprehensive scientific evaluation of post-deployment goals. We assessed the effectiveness of estuarine artificial reefs as a fisheries enhancement initiative; described the diversity and abundance of species associated with them, and detailed the patterns of colonization and community development associated with an artificial reef deployment in Lake Macquarie, a large coastal barrier lagoon on the southeast coast of Australia. Six artificial reefs (one artificial reef group), constructed from artificial reef units (Reef Balls®), were deployed in December 2005 and sampled six times per season over two years using baited remote underwater video (BRUV). Colonization of the artificial reef group was relatively rapid with the majority of species identified over the two-year study period observed within the first year post-deployment. Overall, 27 species from 17 families were identified. Key colonising species included Pelates sexlineatus (Terapontidae), Acanthopagrus australis (Sparidae), Pagrus auratus (Sparidae) and Rhabdosargus sarba (Sparidae). Species richness showed evidence of potential seasonal fluctuations, being higher in warm water months (Summer/Autumn), and lower in the colder water months (Winter/Spring), while species diversity increased significantly with reef age. Fish assemblage composition remained relatively stable after the first year of sampling, with few discernible patterns in assemblage structure evident after the first year. Distinct separation in reef age groupings was evident during the second year of sampling; a pattern primarily driven by a decrease in abundance of P. sexlineatus, a result of the isolated nature of the artificial reefs and the interrelated effects of density dependence and predation.
Linguística Aplicada: uma identidade construida nos CBLA
Authors: Archanjo Renata
Published: October 2011

Este artigo objetiva investigar a Linguística Aplicada (LA) como um campo de estudos produtor de conhecimento que tem sofrido muitas transformações ao longo de sua trajetória de busca de uma identidade própria. Tais transformações são recuperadas nas vozes de suas pesquisas ao longo dos anos. Assim, esse estudo analisa o percurso histórico da LA, com base na produção científica apresentada nos Congressos Brasileiros de Linguística Aplicada (CBLA), buscando compreender os significados revelados pelas vozes sociais que constituem o discurso sobre seu fazer científico. A análise da transformação das áreas e subáreas temáticas de estudo nesse recorte temporal apontam para a diversidade e a riqueza dos caminhos desse campo de saber que lhe configuram uma identidade própria e única.