865 research outputs found

    Electromagnetic wave refraction at an interface of a double wire medium

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    Plane-wave reflection and refraction at an interface with a double wire medium is considered. The problem of additional boundary conditions (ABC) in application to wire media is discussed and an ABC-free approach, known in the solid state physics, is used. Expressions for the fields and Poynting vectors of the refracted waves are derived. Directions and values of the power density flow of the refracted waves are found and the conservation of the power flow through the interface is checked. The difference between the results, given by the conventional model of wire media and the model, properly taking into account spatial dispersion, is discussed.Comment: 17 pages, 11 figure

    Genetically altered AMPA-type glutamate receptor kinetics in interneurons disrupt long-range synchrony of gamma oscillation

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    Gamma oscillations synchronized between distant neuronal populations may be critical for binding together brain regions devoted to common processing tasks. Network modeling predicts that such synchrony depends in part on the fast time course of excitatory postsynaptic potentials (EPSPs) in interneurons, and that even moderate slowing of this time course will disrupt synchrony. We generated mice with slowed interneuron EPSPs by gene targeting, in which the gene encoding the 67-kDa form of glutamic acid decarboxylase (GAD67) was altered to drive expression of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptor subunit GluR-B. GluR-B is a determinant of the relatively slow EPSPs in excitatory neurons and is normally expressed at low levels in γ-aminobutyric acid (GABA)ergic interneurons, but at high levels in the GAD-GluR-B mice. In both wild-type and GAD-GluR-B mice, tetanic stimuli evoked gamma oscillations that were indistinguishable in local field potential recordings. Remarkably, however, oscillation synchrony between spatially separated sites was severely disrupted in the mutant, in association with changes in interneuron firing patterns. The congruence between mouse and model suggests that the rapid time course of AMPA receptor-mediated EPSPs in interneurons might serve to allow gamma oscillations to synchronize over distance

    Actin/alpha-actinin-dependent transport of AMPA receptors in dendritic spines: role of the PDZ-LIM protein RIL

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    The efficacy of excitatory transmission in the brain depends to a large extent on synaptic AMPA receptors, hence the importance of understanding the delivery and recycling of the receptors at the synaptic sites. Here we report a novel regulation of the AMPA receptor transport by a PDZ (postsynaptic density-95/Drosophila disc large tumor suppressor zona occludens 1) and LIM (Lin11/rat Isl-1/Mec3) domain-containing protein, RIL (reversion-induced LIM protein). We show that RIL binds to the AMPA glutamate receptor subunit GluR-A C-terminal peptide via its LIM domain and to alpha-actinin via its PDZ domain. RIL is enriched in the postsynaptic density fraction isolated from rat forebrain, strongly localizes to dendritic spines in cultured neurons, and coprecipitates, together with alpha-actinin, in a protein complex isolated by immunoprecipitation of AMPA receptors from forebrain synaptosomes. Functionally, in heterologous cells, RIL links AMPA receptors to the alpha-actinin/actin cytoskeleton, an effect that appears to apply selectively to the endosomal surface-internalized population of the receptors. In cultured neurons, an overexpression of recombinant RIL increases the accumulation of AMPA receptors in dendritic spines, both at the total level, as assessed by immunodetection of endogenous GluR-A-containing receptors, and at the synaptic surface, as assessed by recording of miniature EPSCs. Our results thus indicate that RIL directs the transport of GluR-A-containing AMPA receptors to and/or within dendritic spines, in an alpha-actinin/actin-dependent manner, and that such trafficking function promotes the synaptic accumulation of the receptors

    O impacto de primeiro ano de tratamento com dornase alfa nos parâmetros clínicos de pacientes com fibrose cística: estudo multicêntrico brasileiro

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    OBJECTIVE:To describe the clinical impact of the first year treatment with dornase alfa, according to age groups, in a cohort of Brazilian Cystic Fibrosis (CF) patients.METHODS:The data on 152 eligible patients, from 16 CF reference centers, that answered the medical questionnaires and performed laboratory tests at baseline (T0), and at six (T2) and 12 (T4) months after dornase alfa initiation, were analyzed. Three age groups were assessed: six to 11, 12 to 13, and >14 years. Pulmonary tests, airway microbiology, emergency room visits, hospitalizations, emergency and routine treatments were evaluated. Student's t-test, chi-square test and analysis of variance were used when appropriated.RESULTS:Routine treatments were based on respiratory physical therapy, regular exercises, pancreatic enzymes, vitamins, bronchodilators, corticosteroids, and antibiotics. In the six months prior the study (T0 phase), hospitalizations for pulmonary exacerbations occurred in 38.0, 10.0 and 61.4% in the three age groups, respectively. After one year of intervention, there was a significant reduction in the number of emergency room visits in the six to 11 years group. There were no significant changes in forced expiratory volume in one second (VEF1), in forced vital capacity (FVC), in oxygen saturation (SpO2), and in Tiffenau index for all age groups. A significant improvement in Shwachman-Kulczychi score was observed in the older group. In the last six months of therapy, chronic or intermittent colonization by P. aeruginosa was detected in 75.0, 71.4 and 62.5% of the studied groups, respectively, while S. aureus colonization was identified in 68.6, 66.6 and 41.9% of the cases.CONCLUSIONS:The treatment with dornase alfa promoted the maintenance of pulmonary function parameters and was associated with a significant reduction of emergency room visits due to pulmonary exacerbations in the six to 11 years age group, with better clinical scores in the >14 age group, one year after the intervention.OBJETIVO:Relatar el impacto clínico del primer año de tratamiento con dornasa alfa conforme a la franja de edad, en una cohorte de pacientes brasileños con fibrosis quística (FC).MÉTODOS:El presente estudio analizó datos de 152 pacientes elegibles, de 16 centros de referencia para FC, los que contestaron a los cuestionarios clínicos y realizaron pruebas laboratoriales, al inicio del tratamiento con la dornasa alfa (T0) y después de 6 (T2) y 12 (T4) meses de la intervención. Se analizaron 3 grupos etarios: 6-11, 12-13 e >14 años de edad. Se evaluaron las pruebas pulmonares, la microbiología de vías aéreas, las atenciones de emergencia, hospitalizaciones y tratamientos emergenciales y de rutina. Las estadísticas descriptivas, pruebas t y chi-cuadrado y ANOVA fueron usadas cuando pertinentes.RESULTADOS:El tratamiento regular se basó en la fisioterapia respiratoria, ejercicios regulares, encimas pancreáticas, vitaminas, broncodilatadores, corticosteroides y antibióticos. En los 6 meses anteriores al estudio (fase T0), las hospitalizaciones por exacerbación pulmonar ocurrieron en 38, 10 y 61,4%, respectivamente, para las tres franjas de edad analizadas. En el grupo 6-11 años, hubo reducción significativa de atenciones de emergencia después de 1 año de tratamiento. No hubo modificaciones significativas de volumen espiratorio forzado en el 1er segundo (VEF1), capacidad vital forzada (CVF), saturación de oxígeno (SpO)2 e índice de Tiffeneau, en todos grupos. El escore de Schwachman-Kulczychi mejoró significativamente en el grupo de más edad. Los últimos 6 meses de tratamiento, la colonización crónica o intermitente por P. aeruginosa fue detectada en el 75, 71,4 y 62,5%, respectivamente, mientras que por S. aureus ocurrió en 68,6, 66,6 y 41,9% de los casos en cada grupo de edad.CONCLUSIONES:La intervención con dornasa alfa resultó en mantenimiento de los parámetros pulmonares y fue asociada a la reducción significativa de visitas a la emergencia por exacerbación pulmonar en el grupo de 6 a 11 años de edad, con mejora del escore clínico en el grupo >14 años de edad, al final de un año de estudio.OBJETIVO:Relatar o impacto clínico do primeiro ano de tratamento com dornase alfa de acordo com a faixa etária, numa coorte de pacientes brasileiros com fibrose cística (FC).MÉTODOS:O presente estudo analisou dados de 152 pacientes elegíveis, de 16 centros de referência para FC, os quais responderam aos questionários clínicos e realizaram testes laboratoriais, ao início do tratamento com dornase alfa (T0) e após seis (T2) e 12 (T4) meses da intervenção. Analisaram-se três grupos etários: seis a 11, 12 a 13 e >14 anos de idade. Avaliaram-se os testes pulmonares, a microbiologia de vias aéreas, os atendimentos de emergência, as hospitalizações e os tratamentos emergenciais e rotineiros. O teste t de Student, o qui-quadrado e a análise de variância foram usados quando pertinentes.RESULTADOS:O tratamento baseou-se em fisioterapia respiratória, exercícios regulares, enzimas pancreáticas, vitaminas, broncodilatadores, corticosteroides e antibióticos. Nos seis meses anteriores ao estudo (fase T0), as hospitalizações por exacerbação pulmonar ocorreram em 38,0, 10,0 e 61,4%, respectivamente para as três faixas etárias analisadas. No grupo de seis a 11 anos, houve redução significativa de atendimentos de emergência após um ano de tratamento. Não houve modificações significativas de volume expiratório forçado no primeiro segundo (VEF1), capacidade vital forçada (CVF), saturação de oxigênio (SpO)2 e índice de Tiffeneau em todos os grupos. O escore de Shwachman-Kulczychi melhorou significativamente no grupo de mais idade. Nos últimos seis meses de tratamento, a colonização crônica ou intermitente por P.aeruginosa foi detectada em 75,0, 71,4 e 62,5%, respectivamente, enquanto a colonização por S.aureus ocorreu em 68,6, 66,6 e 41,9% dos casos em cada grupo etário.CONCLUSÕES:A intervenção com dornase alfa resultou em manutenção dos parâmetros pulmonares e associou-se à redução significativa de visitas à emergência por exacerbação pulmonar no grupo de seis a 11 anos de idade, com melhora do escore clínico no grupo >14 anos de idade ao final de um ano de estudo.Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina (EPM)Universidade Federal do Rio Grande do Sul Faculdade de MedicinaSecretaria da Saúde da Bahia Hospital Especializado Octávio MangabeiraUniversidade de São Paulo Faculdade de Medicina Hospital das ClínicasHospital de Base do Distrito FederalUNIFESP, EPMSciEL

    Use of program products for engineering graphics

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    В работе проведен анализ современных методов повышения эффективности преподавания инженерной графики, используя на занятиях современные технические средства обучения и компьютерные технологии.The analysis of modern methods to improve the effectiveness of engineering graphics teaching using modern teaching aids and computer technology

    Язык духов: параллели между рифмованной прозой (саджʻ) доисламских арабских прорицателей и речевым поведением шаманов

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    The speech behavior of soothsayers (kuhhān), who lived in pre-Islamic Arabia, was characterized by the use of rhymed and rhythmic prose, the formulaic structure of utterances and their enigmatic nature. Furthermore, their speech was ecstatically performed and featured a specific language that was different from the generally accepted mode of everyday communication. As a consequence, their utterances were perceived by their audiences as emanating from supernatural beings. The article draws a parallel between the speech peculiarities of the kuhhān and texts that serve for ‘communication’ with spirits in shamanic/shamanistic cultures. From a functional point of view, in both cases the texts exhibit a number of distinctive properties that mark sacred pronouncements dictated by otherworldly forces. There are also similarities in the contexts and circumstances of text production of soothsayers and shamans. The conclusions of the article can serve as another argument in favor of a typological affinity between these two groups of religious specialists. This affinity has previously been examined mainly through the prism of their social functions and non-verbal behavior. This article, on the other hand, emphasizes the linguistic characteristics of this affinity

    DANSSino: a pilot version of the DANSS neutrino detector

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    DANSSino is a reduced pilot version of a solid-state detector of reactor antineutrinos (to be created within the DANSS project and installed under the industrial 3 GW(th) reactor of the Kalinin Nuclear Power Plant -- KNPP). Numerous tests performed at a distance of 11 m from the reactor core demonstrate operability of the chosen design and reveal the main sources of the background. In spite of its small size (20x20x100 ccm), the pilot detector turned out to be quite sensitive to reactor antineutrinos, detecting about 70 IBD events per day with the signal-to-background ratio about unity.Comment: 16 pages, 11 figures, 3 tables. arXiv admin note: substantial text overlap with arXiv:1304.369

    Use of program products for engineering graphics

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    В работе проведен анализ современных методов повышения эффективности преподавания инженерной графики, используя на занятиях современные технические средства обучения и компьютерные технологии.The analysis of modern methods to improve the effectiveness of engineering graphics teaching using modern teaching aids and computer technology
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