Sample records for scanning em sem
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Directory of Open Access Journals (Sweden)
Masaaki Kuwajima
Full Text Available Transmission-mode scanning electron microscopy (tSEM on a field emission SEM platform was developed for efficient and cost-effective imaging of circuit-scale volumes from brain at nanoscale resolution. Image area was maximized while optimizing the resolution and dynamic range necessary for discriminating key subcellular structures, such as small axonal, dendritic and glial processes, synapses, smooth endoplasmic reticulum, vesicles, microtubules, polyribosomes, and endosomes which are critical for neuronal function. Individual image fields from the tSEM system were up to 4,295 µm(2 (65.54 µm per side at 2 nm pixel size, contrasting with image fields from a modern transmission electron microscope (TEM system, which were only 66.59 µm(2 (8.160 µm per side at the same pixel size. The tSEM produced outstanding images and had reduced distortion and drift relative to TEM. Automated stage and scan control in tSEM easily provided unattended serial section imaging and montaging. Lens and scan properties on both TEM and SEM platforms revealed no significant nonlinear distortions within a central field of ∼100 µm(2 and produced near-perfect image registration across serial sections using the computational elastic alignment tool in Fiji/TrakEM2 software, and reliable geometric measurements from RECONSTRUCT™ or Fiji/TrakEM2 software. Axial resolution limits the analysis of small structures contained within a section (∼45 nm. Since this new tSEM is non-destructive, objects within a section can be explored at finer axial resolution in TEM tomography with current methods. Future development of tSEM tomography promises thinner axial resolution producing nearly isotropic voxels and should provide within-section analyses of structures without changing platforms. Brain was the test system given our interest in synaptic connectivity and plasticity; however, the new tSEM system is readily applicable to other biological systems.
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Quantifying Golgi structure using EM: combining volume-SEM and stereology for higher throughput.
Ferguson, Sophie; Steyer, Anna M; Mayhew, Terry M; Schwab, Yannick; Lucocq, John Milton
2017-06-01
Investigating organelles such as the Golgi complex depends increasingly on high-throughput quantitative morphological analyses from multiple experimental or genetic conditions. Light microscopy (LM) has been an effective tool for screening but fails to reveal fine details of Golgi structures such as vesicles, tubules and cisternae. Electron microscopy (EM) has sufficient resolution but traditional transmission EM (TEM) methods are slow and inefficient. Newer volume scanning EM (volume-SEM) methods now have the potential to speed up 3D analysis by automated sectioning and imaging. However, they produce large arrays of sections and/or images, which require labour-intensive 3D reconstruction for quantitation on limited cell numbers. Here, we show that the information storage, digital waste and workload involved in using volume-SEM can be reduced substantially using sampling-based stereology. Using the Golgi as an example, we describe how Golgi populations can be sensed quantitatively using single random slices and how accurate quantitative structural data on Golgi organelles of individual cells can be obtained using only 5-10 sections/images taken from a volume-SEM series (thereby sensing population parameters and cell-cell variability). The approach will be useful in techniques such as correlative LM and EM (CLEM) where small samples of cells are treated and where there may be variable responses. For Golgi study, we outline a series of stereological estimators that are suited to these analyses and suggest workflows, which have the potential to enhance the speed and relevance of data acquisition in volume-SEM.
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Sonomura, Takahiro; Furuta, Takahiro; Nakatani, Ikuko; Yamamoto, Yo; Honma, Satoru; Kaneko, Takeshi
2014-11-01
Ten years have passed since a serial block-face scanning electron microscopy (SBF-SEM) method was developed [1]. In this innovative method, samples were automatically sectioned with an ultramicrotome placed inside a scanning electron microscope column, and the block surfaces were imaged one after another by SEM to capture back-scattered electrons. The contrast-inverted images obtained by the SBF-SEM were very similar to those acquired using conventional TEM. SFB-SEM has made easy to acquire image stacks of the transmission electron microscopy (TEM) in the mesoscale, which is taken with the confocal laser-scanning microcopy(CF-LSM).Furthermore, serial-section SEM has been combined with the focused ion beam (FIB) milling method [2]. FIB-incorporated SEM (FIB-SEM) has enabled the acquisition of three-dimensional images with a higher z-axis resolution com- pared to ultramicrotome-equipped SEM.We tried immunocytochemistry for FIB-SEM and correlated this immunoreactivity with that in CF-LSM. Dendrites of neurons in the rat neostriatum were visualized using a recombinant viral vector. Moreover, the thalamostriatal afferent terminals were immunolabeled with Cy5 fluorescence for vesicular glutamate transporter 2 (VGluT2). After detection of the sites of terminals apposed to the dendrites by using CF-LSM, GFP and VGluT2 immunoreactivities were further developed for EM by using immunogold/silver enhancement and immunoperoxidase/diaminobenzidine (DAB) methods, respectively.We showed that conventional immuno-cytochemical staining for TEM was applicable to FIB-SEM. Furthermore, several synaptic contacts, which were thought to exist on the basis of CF-LSM findings, were confirmed with FIB-SEM, revealing the usefulness of the combined method of CF-LSM and FIB-SEM. © The Author 2014. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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Role of scanning electron microscope )SEM) in metal failure analysis
International Nuclear Information System (INIS)
Shaiful Rizam Shamsudin; Hafizal Yazid; Mohd Harun; Siti Selina Abd Hamid; Nadira Kamarudin; Zaiton Selamat; Mohd Shariff Sattar; Muhamad Jalil
2005-01-01
Scanning electron microscope (SEM) is a scientific instrument that uses a beam of highly energetic electrons to examine the surface and phase distribution of specimens on a micro scale through the live imaging of secondary electrons (SE) and back-scattered electrons (BSE) images. One of the main activities of SEM Laboratory at MINT is for failure analysis on metal part and components. The capability of SEM is excellent for determining the root cause of metal failures such as ductility or brittleness, stress corrosion, fatigue and other types of failures. Most of our customers that request for failure analysis are from local petrochemical plants, manufacturers of automotive components, pipeline maintenance personnel and engineers who involved in the development of metal parts and component. This paper intends to discuss some of the technical concepts in failure analysis associated with SEM. (Author)
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Wille, Guillaume; Hellal, Jennifer; Ollivier, Patrick; Richard, Annie; Burel, Agnes; Jolly, Louis; Crampon, Marc; Michel, Caroline
2017-12-01
Understanding biofilm interactions with surrounding substratum and pollutants/particles can benefit from the application of existing microscopy tools. Using the example of biofilm interactions with zero-valent iron nanoparticles (nZVI), this study aims to apply various approaches in biofilm preparation and labeling for fluorescent or electron microscopy and energy dispersive X-ray spectrometry (EDS) microanalysis for accurate observations. According to the targeted microscopy method, biofilms were sampled as flocs or attached biofilm, submitted to labeling using 4',6-diamidino-2-phenylindol, lectins PNA and ConA coupled to fluorescent dye or gold nanoparticles, and prepared for observation (fixation, cross-section, freezing, ultramicrotomy). Fluorescent microscopy revealed that nZVI were embedded in the biofilm structure as aggregates but the resolution was insufficient to observe individual nZVI. Cryo-scanning electron microscopy (SEM) observations showed nZVI aggregates close to bacteria, but it was not possible to confirm direct interactions between nZVI and cell membranes. Scanning transmission electron microscopy in the SEM (STEM-in-SEM) showed that nZVI aggregates could enter the biofilm to a depth of 7-11 µm. Bacteria were surrounded by a ring of extracellular polymeric substances (EPS) preventing direct nZVI/membrane interactions. STEM/EDS mapping revealed a co-localization of nZVI aggregates with lectins suggesting a potential role of EPS in nZVI embedding. Thus, the combination of divergent microscopy approaches is a good approach to better understand and characterize biofilm/metal interactions.
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Thermal Studies of Zn(II, Cd(II and Hg(II Complexes of Some <em>N-Alkyl-N>-Phenyl-Dithiocarbamates
Directory of Open Access Journals (Sweden)
Peter A. Ajibade
2012-07-01
Full Text Available The thermal decomposition of Zn(II, Cd(II and Hg(II complexes of <em>N-ethyl-N>-phenyl and <em>N-butyl-N>-phenyl dithiocarbamates have been studied using thermogravimetric analysis (TGA and differential scanning calorimetry (DSC. The products of the decomposition, at two different temperatures, were further characterized by scanning electron microscopy (SEM and energy-dispersive X-ray spectroscopy (EDX. The results show that while the zinc and cadmium complexes undergo decomposition to form metal sulphides, and further undergo oxidation forming metal oxides as final products, the mercury complexes gave unstable volatiles as the final product.
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Tondare, Vipin N; Villarrubia, John S; Vlada R, András E
2017-10-01
Three-dimensional (3D) reconstruction of a sample surface from scanning electron microscope (SEM) images taken at two perspectives has been known for decades. Nowadays, there exist several commercially available stereophotogrammetry software packages. For testing these software packages, in this study we used Monte Carlo simulated SEM images of virtual samples. A virtual sample is a model in a computer, and its true dimensions are known exactly, which is impossible for real SEM samples due to measurement uncertainty. The simulated SEM images can be used for algorithm testing, development, and validation. We tested two stereophotogrammetry software packages and compared their reconstructed 3D models with the known geometry of the virtual samples used to create the simulated SEM images. Both packages performed relatively well with simulated SEM images of a sample with a rough surface. However, in a sample containing nearly uniform and therefore low-contrast zones, the height reconstruction error was ≈46%. The present stereophotogrammetry software packages need further improvement before they can be used reliably with SEM images with uniform zones.
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Encontros e desvios nos semáforos: investigando artistas em Florianópolis/SC
Directory of Open Access Journals (Sweden)
Beatriz S. Albino
2013-03-01
Full Text Available http://dx.doi.org/10.5007/2178-4582.2012v46n2p469 A ideia de investigar artistas que atuam em semáforos de Florianópolis/SC teve sua origem em um estranhamento que nos fez vê-los na forma de uma alteridade radical. A pesquisa etnográfica permitiu descobrir relações simbólicas de pertencimentoe de desvio entre os artistas, destacando-se a figura de um “outro”, próximo, mas perigoso, que partilha simbolicamente os semáforos: o micróbio, estrangeiro que faria confundir o artista com a marginalidade. No semáforo ocorre também, no entanto, a reafirmação, por meio das performances dos artistas, do que deles é esperado: a comicidade, o virtuosismo, a aparência adequada.
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A Teoria dos Blocos Semânticos em revisão
Directory of Open Access Journals (Sweden)
Julio Cesar Machado
2017-08-01
Full Text Available A Teoria dos Blocos Semânticos ocupa lugar significativo nos trabalhos mundiais em Semântica, Argumentação e Enunciação, dentre outros. Por isso sua pertinência para a Linguística reclama uma reflexão. O presente trabalho pretende refletir algumas reformulações na Teoria dos Blocos Semânticos nas últimas duas décadas, a saber: (a polifonia, (b bloco semântico, e (c quadrado argumentativo. Especificamente, trataremos das seguintes relações: (a’ da Teoria Polifônica da Enunciação à Teoria Argumentativa da Polifonia; (b’ do bloco semântico ao semi-bloco; e (c’ do quadrado argumentativo ao cubo argumentativo. A necessidade deste trabalho é duplamente justificada: (i devido à constante revisão teórica do arcabouço teórico deste saber, sobretudo na sua última década, característica de Marion Carel e de Oswald Ducrot; e (ii pela falta de tradução/circulação no Brasil de obras fundamentais no que tange à re-elaboração das noções chaves desta teoria.
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Protocolo para a distribuição de informações de canais em redes em malha sem fio
Directory of Open Access Journals (Sweden)
Roni Francis Shigueta
2014-04-01
Full Text Available Este artigo apresenta um protocolo para a distribuição de informações de canais em uma rede em malha sem fio. O canal corresponde à faixa de frequência na qual dois dispositivos sem fio (nós da rede podem se comunicar. O protocolo apresentado permite criar um repositório que contém os canais que estão disponíveis em um dispositivo para que se comunique com o seu nó vizinho. A partir das informações desse repositório, os dispositivos podem tomar decisões de alocação de canais, baseadas em algum critério, como por exemplo, a menor interferência gerada na rede. Dependendo da quantidade de canais disponíveis, é possível atribuir canais diferentes aos enlaces da rede (par de nós, permitindo transmissões simultâneas. A simulação do protocolo é realizada por meio de canais de frequência do padrão IEEE 802.11b. Apesar das simulações serem realizadas nesse padrão, o protocolo pode ser adaptado para operar em outras faixas de frequência. Os resultados demonstram que a partir dos valores dos canais transmitidos através de mensagens de hello, é possível encontrar os canais comuns entre dois nós, realizando a intersecção entre a lista de canais do nó vizinho com a lista do nó local.
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Stanley, A. G.; Gauthier, M. K.
1977-01-01
A successful diagnostic technique was developed using a scanning electron microscope (SEM) as a precision tool to determine ionization effects in integrated circuits. Previous SEM methods radiated the entire semiconductor chip or major areas. The large area exposure methods do not reveal the exact components which are sensitive to radiation. To locate these sensitive components a new method was developed, which consisted in successively irradiating selected components on the device chip with equal doses of electrons /10 to the 6th rad (Si)/, while the whole device was subjected to representative bias conditions. A suitable device parameter was measured in situ after each successive irradiation with the beam off.
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Rodrigues, David Manuel Cardoso
2013-01-01
Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores O rápido desenvolvimento da microtecnologia e microelectrónica tem vindo a contribuir de forma decisiva para uma crescente utilização de sensores, sejam eles com ou sem fios, o que permitirá interagir mais eficientemente com o meio envolvente, em consequência de mais e melhor medição e atuação. Neste contexto, as redes de sensores sem fios (WSNs) estão a emergir como uma das grandes e mais impo...
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SEM Analysis of Surface Impact on Biofilm Antibiotic Treatment.
Gomes, Luciana Calheiros; Mergulhão, Filipe José
2017-01-01
The aim of this work was to use scanning electron microscopy (SEM) to investigate the effect of ampicillin treatment on Escherichia coli biofilms formed on two surface materials with different properties, silicone (SIL) and glass (GLA). Epifluorescence microscopy (EM) was initially used to assess biofilm formation and killing efficiency on both surfaces. This technique showed that higher bacterial colonization was obtained in the hydrophobic SIL than in the hydrophilic GLA. It has also shown that higher biofilm inactivation was attained for GLA after the antibiotic treatment (7-log reduction versus 1-log reduction for SIL). Due to its high resolution and magnification, SEM enabled a more detailed analysis of the antibiotic effect on biofilm cells, complementing the killing efficiency information obtained by EM. SEM micrographs revealed that ampicillin-treated cells have an elongated form when compared to untreated cells. Additionally, it has shown that different materials induced different levels of elongation on cells exposed to antibiotic. Biofilms formed on GLA showed a 37% higher elongation than those formed on SIL. Importantly, cell elongation was related to viability since ampicillin had a higher bactericidal effect on GLA-formed biofilms. These findings raise the possibility of using SEM for understanding the efficacy of antimicrobial treatments by observation of biofilm morphology.
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A fluorescence scanning electron microscope
International Nuclear Information System (INIS)
Kanemaru, Takaaki; Hirata, Kazuho; Takasu, Shin-ichi; Isobe, Shin-ichiro; Mizuki, Keiji; Mataka, Shuntaro; Nakamura, Kei-ichiro
2009-01-01
Fluorescence techniques are widely used in biological research to examine molecular localization, while electron microscopy can provide unique ultrastructural information. To date, correlative images from both fluorescence and electron microscopy have been obtained separately using two different instruments, i.e. a fluorescence microscope (FM) and an electron microscope (EM). In the current study, a scanning electron microscope (SEM) (JEOL JXA8600 M) was combined with a fluorescence digital camera microscope unit and this hybrid instrument was named a fluorescence SEM (FL-SEM). In the labeling of FL-SEM samples, both Fluolid, which is an organic EL dye, and Alexa Fluor, were employed. We successfully demonstrated that the FL-SEM is a simple and practical tool for correlative fluorescence and electron microscopy.
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Horstmann, Heinz; Körber, Christoph; Sätzler, Kurt; Aydin, Daniel; Kuner, Thomas
2012-01-01
High resolution, three-dimensional (3D) representations of cellular ultrastructure are essential for structure function studies in all areas of cell biology. While limited subcellular volumes have been routinely examined using serial section transmission electron microscopy (ssTEM), complete ultrastructural reconstructions of large volumes, entire cells or even tissue are difficult to achieve using ssTEM. Here, we introduce a novel approach combining serial sectioning of tissue with scanning electron microscopy (SEM) using a conductive silicon wafer as a support. Ribbons containing hundreds of 35 nm thick sections can be generated and imaged on the wafer at a lateral pixel resolution of 3.7 nm by recording the backscattered electrons with the in-lens detector of the SEM. The resulting electron micrographs are qualitatively comparable to those obtained by conventional TEM. S(3)EM images of the same region of interest in consecutive sections can be used for 3D reconstructions of large structures. We demonstrate the potential of this approach by reconstructing a 31.7 µm(3) volume of a calyx of Held presynaptic terminal. The approach introduced here, Serial Section SEM (S(3)EM), for the first time provides the possibility to obtain 3D ultrastructure of large volumes with high resolution and to selectively and repetitively home in on structures of interest. S(3)EM accelerates process duration, is amenable to full automation and can be implemented with standard instrumentation.
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Directory of Open Access Journals (Sweden)
Heinz Horstmann
Full Text Available High resolution, three-dimensional (3D representations of cellular ultrastructure are essential for structure function studies in all areas of cell biology. While limited subcellular volumes have been routinely examined using serial section transmission electron microscopy (ssTEM, complete ultrastructural reconstructions of large volumes, entire cells or even tissue are difficult to achieve using ssTEM. Here, we introduce a novel approach combining serial sectioning of tissue with scanning electron microscopy (SEM using a conductive silicon wafer as a support. Ribbons containing hundreds of 35 nm thick sections can be generated and imaged on the wafer at a lateral pixel resolution of 3.7 nm by recording the backscattered electrons with the in-lens detector of the SEM. The resulting electron micrographs are qualitatively comparable to those obtained by conventional TEM. S(3EM images of the same region of interest in consecutive sections can be used for 3D reconstructions of large structures. We demonstrate the potential of this approach by reconstructing a 31.7 µm(3 volume of a calyx of Held presynaptic terminal. The approach introduced here, Serial Section SEM (S(3EM, for the first time provides the possibility to obtain 3D ultrastructure of large volumes with high resolution and to selectively and repetitively home in on structures of interest. S(3EM accelerates process duration, is amenable to full automation and can be implemented with standard instrumentation.
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Developing 3D SEM in a broad biological context
Kremer, A; Lippens, S; Bartunkova, S; Asselbergh, B; Blanpain, C; Fendrych, M; Goossens, A; Holt, M; Janssens, S; Krols, M; Larsimont, J-C; Mc Guire, C; Nowack, MK; Saelens, X; Schertel, A; Schepens, B; Slezak, M; Timmerman, V; Theunis, C; Van Brempt, R; Visser, Y; GuÉRin, CJ
2015-01-01
When electron microscopy (EM) was introduced in the 1930s it gave scientists their first look into the nanoworld of cells. Over the last 80 years EM has vastly increased our understanding of the complex cellular structures that underlie the diverse functions that cells need to maintain life. One drawback that has been difficult to overcome was the inherent lack of volume information, mainly due to the limit on the thickness of sections that could be viewed in a transmission electron microscope (TEM). For many years scientists struggled to achieve three-dimensional (3D) EM using serial section reconstructions, TEM tomography, and scanning EM (SEM) techniques such as freeze-fracture. Although each technique yielded some special information, they required a significant amount of time and specialist expertise to obtain even a very small 3D EM dataset. Almost 20 years ago scientists began to exploit SEMs to image blocks of embedded tissues and perform serial sectioning of these tissues inside the SEM chamber. Using first focused ion beams (FIB) and subsequently robotic ultramicrotomes (serial block-face, SBF-SEM) microscopists were able to collect large volumes of 3D EM information at resolutions that could address many important biological questions, and do so in an efficient manner. We present here some examples of 3D EM taken from the many diverse specimens that have been imaged in our core facility. We propose that the next major step forward will be to efficiently correlate functional information obtained using light microscopy (LM) with 3D EM datasets to more completely investigate the important links between cell structures and their functions. Lay Description Life happens in three dimensions. For many years, first light, and then EM struggled to image the smallest parts of cells in 3D. With recent advances in technology and corresponding improvements in computing, scientists can now see the 3D world of the cell at the nanoscale. In this paper we present the
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Roteamento em redes em malha sem fio com balanceamento de carga e caminhos mais curtos
Mello, Micael Oliveira Massula Carvalho de
2014-01-01
Redes em Malha Sem Fio - Wireless Mesh Networks (WMNs) são infraestruturas com propriedades autonômicas, como auto-organização e autorrecuperação, que podem ser implementadas com tecnologias amplamente disponíveis e de custo acessível. Além de suas aplicações atuais, como redes comunitárias e redes de acesso à Internet, as WMNs podem auxiliar na comunicação de Internet das Coisas e constituir infraestruturas robustas para redes inteligentes de energia, dentre outros usos. No en...
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Estudo da sintomatologia depressiva e ansiosa em crianças com e sem obesidade
Morgado, Joana Alexandra da Silva
2013-01-01
A obesidade infantil constitui um problema de saúde pública, o que motivou a sua classificação pela WHO como “epidemia do seculo XXI”. Como se não bastasse, surge sempre associada ao aumento quer da mortalidade, quer da morbilidade. Este estudo procura perceber em que medida as crianças com obesidade infantil diferem das crianças sem obesidade em termos de sintomatologia depressiva e ansiosa. O desenho do estudo é de natureza transversal e comparativa. A amostra é composta por 85 crianças, co...
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Czech Academy of Sciences Publication Activity Database
Havrdová, M.; Poláková, K.; Skopalík, J.; Vůjtek, M.; Mokdad, A.; Homolková, M.; Tuček, J.; Nebesářová, Jana; Zbořil, R.
2014-01-01
Roč. 67, DEC 2014 (2014), s. 149-154 ISSN 0968-4328 Institutional support: RVO:60077344 Keywords : Field emission scanning electronmicroscopy (FE-SEM) * Stem cells * Iron oxide nanoparticles * Cellular morphology * Endosomes * Cell uptake Subject RIV: FD - Oncology ; Hematology Impact factor: 1.988, year: 2014
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Equivalência semântica e confiabilidade da versão em português da Bergen Facebook Addiction Scale
Directory of Open Access Journals (Sweden)
Hugo Rafael de Souza e Silva
2015-03-01
Full Text Available Objetivo Avaliar a equivalência semântica e a confiabilidade da Bergen Facebook Addiction Scale para o português (Brasil. Métodos O processo consistiu em cinco passos: tradução; retradução; revisão técnica e avaliação da equivalência semântica por profissionais; avaliação do instrumento por compreensão verbal por uma amostra de profissionais (n = 10 e de estudantes (n = 37; análise de consistência interna e estabilidade por meio do coeficiente de Cronbach e coeficiente de correlação intraclasse (CCI respectivamente, em uma amostra de 359 estudantes de graduação. Resultados O instrumento apresentou no fim um excelente nível de compreensão verbal pela população-alvo, alfa de Cronbach de 0,92 e CCI de 0,81. Conclusão A versão adaptada do instrumento para o uso em nosso ambiente resultou em um instrumento equivalente do ponto de visão de equivalência semântica, assegurando a transferência do significado geral e referencial, mantendo níveis satisfatórios de confiabilidade.
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NGAL urinária em pacientes sem e com lesão renal aguda em unidade de terapia intensiva
Directory of Open Access Journals (Sweden)
Mirian Watanabe
2014-12-01
Full Text Available Objetivo: Avaliar a eficácia diagnóstica e prognóstica da lipocalina associada à gelatinase neutrofílica urinária em pacientes de unidade de terapia intensiva. Métodos: Estudo do tipo coorte, prospectivo, longitudinal desenvolvido em uma unidade de terapia intensiva clínica especializada em cardiologia. Os pacientes foram estratificados segundo os grupos sem e com lesão renal aguda, acompanhados a partir das primeiras 24 horas de internação até a alta hospitalar ou óbito. A creatinina sérica, o fluxo urinário e a lipocalina associada à gelatinase neutrofílica urinária foram coletadas em dois períodos: 24 horas e 48 horas de admissão. Resultados: Foram avaliados 83 pacientes clínicos da unidade de terapia intensiva, com predomínio do gênero masculino (57,8%. Os pacientes foram agrupados em sem lesão renal aguda (N=18, com lesão renal aguda (N=28 ou com lesão renal aguda grave (N=37. Entre os pacientes com lesão renal aguda e lesão renal aguda grave, foram prevalentes os portadores de doenças crônicas, em uso de ventilação mecânica e em terapia de substituição renal, além daqueles com maiores taxas de permanência na unidade de terapia intensiva e hospitalar, e maior mortalidade. O grupo com lesão renal aguda não apresentou alteração significativa da creatinina sérica nas primeiras 24 horas na unidade de terapia intensiva, apesar dos níveis elevados de lipocalina associada à gelatinase neutrofilica urinária demonstrados nos grupos com lesão renal aguda e lesão renal aguda grave (p<0,001. Níveis elevados de lipocalina associada à gelatinase neutrofílica urinária na amostra foram associados ao óbito. Conclusão: A elevação nos níveis de lipocalina associada à gelatinase neutrofílica urinária antecede as variações da creatinina sérica em pacientes com lesão renal aguda e pode ser associada ao óbito.
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Hasegawa, Tomoka; Yamamoto, Tomomaya; Hongo, Hiromi; Qiu, Zixuan; Abe, Miki; Kanesaki, Takuma; Tanaka, Kawori; Endo, Takashi; de Freitas, Paulo Henrique Luiz; Li, Minqi; Amizuka, Norio
2018-04-01
The aim of this study is to demonstrate the application of focused ion beam-scanning electron microscopy, FIB-SEM for revealing the three-dimensional features of osteocytic cytoplasmic processes in metaphyseal (immature) and diaphyseal (mature) trabeculae. Tibiae of eight-week-old male mice were fixed with aldehyde solution, and treated with block staining prior to FIB-SEM observation. While two-dimensional backscattered SEM images showed osteocytes' cytoplasmic processes in a fragmented fashion, three-dimensional reconstructions of FIB-SEM images demonstrated that osteocytes in primary metaphyseal trabeculae extended their cytoplasmic processes randomly, thus maintaining contact with neighboring osteocytes and osteoblasts. In contrast, diaphyseal osteocytes extended thin cytoplasmic processes from their cell bodies, which ran perpendicular to the bone surface. In addition, these osteocytes featured thick processes that branched into thinner, transverse cytoplasmic processes; at some point, however, these transverse processes bend at a right angle to run perpendicular to the bone surface. Osteoblasts also possessed thicker cytoplasmic processes that branched off as thinner processes, which then connected with cytoplasmic processes of neighboring osteocytes. Thus, FIB-SEM is a useful technology for visualizing the three-dimensional structures of osteocytes and their cytoplasmic processes.
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Edmunson, J.; Gaskin, J. A.; Danilatos, G.; Doloboff, I. J.; Effinger, M. R.; Harvey, R. P.; Jerman, G. A.; Klein-Schoder, R.; Mackie, W.; Magera, B.;
2016-01-01
The Miniaturized Variable Pressure Scanning Electron Microscope(MVP-SEM) project, funded by the NASA Planetary Instrument Concepts for the Advancement of Solar System Observations (PICASSO) Research Opportunities in Space and Earth Science (ROSES), will build upon previous miniaturized SEM designs for lunar and International Space Station (ISS) applications and recent advancements in variable pressure SEM's to design and build a SEM to complete analyses of samples on the surface of Mars using the atmosphere as an imaging medium. By the end of the PICASSO work, a prototype of the primary proof-of-concept components (i.e., the electron gun, focusing optics and scanning system)will be assembled and preliminary testing in a Mars analog chamber at the Jet Propulsion Laboratory will be completed to partially fulfill Technology Readiness Level to 5 requirements for those components. The team plans to have Secondary Electron Imaging(SEI), Backscattered Electron (BSE) detection, and Energy Dispersive Spectroscopy (EDS) capabilities through the MVP-SEM.
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Directory of Open Access Journals (Sweden)
Andrzej Kownacki
2015-07-01
Full Text Available The paper reports on the value of scanning electron microscopy (SEM in the taxonomy and morphology of Chironomidae. This method has been relatively rarely used in Chironomidae studies. Our studies suggest that the SEM method provides a lot of new information. For example, the plastron plate of the thoracic horn of Macropelopia nebulosa (Meigen under light microscopy is visible as points, while under SEM we have found that it consists of a reticular structure with holes. By using SEM a more precise picture of the body structure of Chironomidae can be revealed. It allows researchers to explain inconsistencies in the existing descriptions of species. Another advantage of the SEM method is obtaining spatial images of the body and organs of Chironomidae. However, the SEM method also has some limitations. The main problem is dirt or debris (e.g. algae, mud, secretions, mucus, bacteria, etc., which often settles on the external surface of structures, especially those which are uneven or covered with hair. The dirt should be removed after collection of chironomid material because if left in place it can become chemically fixed to various surfaces. It unnecessarily remains at the surface and final microscopic images may contain artifacts that obscure chironomid structures being investigated. In this way many details of the surface are thus unreadable. The results reported here indicate that SEM examination helps us to identify new morphological features and details that will facilitate the identification of species of Chironomidae and may help to clarify the function of various parts of the body. Fast development of electron microscope technique allows us to learn more about structure of different organisms.
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A new method using Scanning Electron Microscopy (SEM) for preparation of anisopterous odonates.
Del Palacio, Alejandro; Sarmiento, Patricia Laura; Javier, Muzón
2017-10-01
Anisopterous odonate male's secondary genitalia is a complex of several structures, among them the vesica spermalis is the most informative with important specific characters. The observation of those characters, mostly of membranous nature, is difficult in the Scanning Electron Microscope due to dehydration and metallization processes. In this contribution, we discuss a new and low cost procedure for the observation of these characters in the SEM, compatible with the most common agents used for preserving specimens. © 2017 Wiley Periodicals, Inc.
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Edmunson, J.; Gaskin, J. A.; Jerman, G. A.; Harvey, R. P.; Doloboff, I. J.; Neidholdt, E. L.
2016-01-01
The Miniaturized Variable Pressure Scanning Electron Microscope (MVP-SEM) project, funded by the NASA Planetary Instrument Concepts for the Advancement of Solar System Observations (PICASSO) Research Opportunities in Space and Earth Sciences (ROSES), will build upon previous miniaturized SEM designs and recent advancements in variable pressure SEM's to design and build a SEM to complete analyses of samples on the surface of Mars using the atmosphere as an imaging medium. This project is a collaboration between NASA Marshall Space Flight Center (MSFC), the Jet Propulsion Laboratory (JPL), electron gun and optics manufacturer Applied Physics Technologies, and small vacuum system manufacturer Creare. Dr. Ralph Harvery and environmental SEM (ESEM) inventor Dr. Gerry Danilatos serve as advisors to the team. Variable pressure SEMs allow for fine (nm-scale) resolution imaging and micron-scale chemical study of materials without sample preparation (e.g., carbon or gold coating). Charging of a sample is reduced or eliminated by the gas surrounding the sample. It is this property of ESEMs that make them ideal for locations where sample preparation is not yet feasible, such as the surface of Mars. In addition, the lack of sample preparation needed here will simplify the sample acquisition process and allow caching of the samples for future complementary payload use.
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Yang, R; Elankumaran, Y; Hijjawi, N; Ryan, U
2015-06-01
A cell-free culture system for Cryptosporidium parvum was analysed using scanning electron microscopy (SEM) to characterise life cycle stages and compare gene expression in cell-free culture and cell culture using HCT-8 cells. Cryptosporidium parvum samples were harvested at 2 h, 8 h, 14 h, 26 h, 50 h, 74 h, 98 h, 122 h and 170 h, chemically fixed and specimens were observed using a Zeiss 1555 scanning electron microscope. The presence of sporozoites, trophozoites and type I merozoites were identified by SEM. Gene expression in cell culture and cell-free culture was studied using reverse transcriptase quantitative PCR (RT-qPCR) of the sporozoite surface antigen protein (cp15), the glycoprotein 900 (gp900), the Cryptosporidium oocyst wall protein (COWP) and 18S ribosomal RNA (rRNA) genes in both cell free and conventional cell culture. In cell culture, cp15 expression peaked at 74 h, gp900 expression peaked at 74 h and 98 h and COWP expression peaked at 50 h. In cell-free culture, CP15 expression peaked at 98 h, gp900 expression peaked at 74 h and COWP expression peaked at 122 h. The present study is the first to compare gene expression of C. parvum in cell culture and cell-free culture and to characterise life cycle stages of C. parvum in cell-free culture using SEM. Findings from this study showed that gene expression patterns in cell culture and cell-free culture were similar but in cell-free culture, gene expression was delayed for CP15 and COWP in cell free culture compared with the cell culture system and was lower. Although three life cycle stageswere conclusively identified, improvements in SEM methodology should lead to the detection of more life cycle stages. Copyright © 2015 Elsevier Inc. All rights reserved.
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Kownacki, Andrzej; Woznicka, Olga; Szarek-Gwiazda, Ewa; Michailova, Paraskeva; Czaplicka, Anna
2017-02-27
In this paper, a study of the morphology of the pupa and male imago of Glyptotendipes (G.) glaucus (Meigen 1818) was carried out, with the aid of a scanning electron microscope (SEM). The SEM provided additional valuable information on the morphology of the species. Adult male head, antenna, wing, leg, abdomen, hypopygium, pupal cephalothorax and abdomen were examined. It is emphasized that SEM was not often used in Chironomidae studies. The present results confirm SEM as a suitable approach in carrying out morphological and taxonomical descriptions of Chironomidae species.
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3D imaging of cells and tissues by focused ion beam/scanning electron microscopy (FIB/SEM).
Drobne, Damjana
2013-01-01
Integration of a scanning electron microscope (SEM) and focused ion beam (FIB) technology into a single FIB/SEM system permits use of the FIB as a nano-scalpel to reveal site-specific subsurface microstructures which can be examined in great detail by SEM. The FIB/SEM technology is widely used in the semiconductor industry and material sciences, and recently its use in the life sciences has been initiated. Samples for FIB/SEM investigation can be either embedded in a plastic matrix, the traditional means of preparation of transmission electron microscopy (TEM) specimens, or simply dried as in samples prepared for SEM imaging. Currently, FIB/SEM is used in the life sciences for (a) preparation by the lift-out technique of lamella for TEM analysis, (b) tomography of samples embedded in a matrix, and (c) in situ site-specific FIB milling and SEM imaging using a wide range of magnifications. Site-specific milling and imaging has attracted wide interest as a technique in structural research of single eukaryotic and prokaryotic cells, small animals, and different animal tissue, but it still remains to be explored more thoroughly. In the past, preparation of samples for site-specific milling and imaging by FIB/SEM has typically adopted the embedding techniques used for TEM samples, and which have been very well described in the literature. Sample preparation protocols for the use of dried samples in FIB/SEM have been less well investigated. The aim of this chapter is to encourage application of FIB/SEM on dried biological samples. A detailed description of conventional dried sample preparation and FIB/SEM investigation of dried biological samples is presented. The important steps are described and illustrated, and direct comparison between embedded and dried samples of same tissues is provided. The ability to discover links between gross morphology of the tissue or organ, surface characteristics of any selected region, and intracellular structural details on the nanometer
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Mapa de energia baseado em predição para redes de sensores sem fio
Raquel Aparecida de Freitas Mini
2004-01-01
O objetivo deste trabalho é construir o mapa de energia de uma rede de sensores sem fio utilizando técnicas de predição. Em mapas de energia baseados em predição, cada nó sensor utiliza algoritmos de predição para modelar sua dissipação de energia com o objetivo de prever seu consumo de energia no futuro. Nesta situação, ao invés de enviar para o nó sorvedouro apenas sua quantidade de energia disponível, cada sensor envia também os parâmetros do modelo que descreve seu consumo de energia. O n...
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Adição de colágeno em pão sem glúten elaborado com farinha de arroz
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Carolina da Silva Graça
2017-02-01
Full Text Available Resumo Os portadores da doença celíaca, uma enteropatia, apresentam intolerância ao glúten e a restrição de alimentos que o contenham mostra-se eficaz na normalização da função intestinal e das manifestações clínicas. O objetivo do presente estudo foi avaliar o efeito da adição de colágeno em pó e em fibra nas características estruturais, tecnológicas e sensoriais de pães sem glúten, elaborados com farinha de arroz. Primeiramente, foram realizadas adições de 2%, 4%, 6% e 8% de colágeno, sob as formas em pó e em fibra, em pães elaborados com farinha de arroz, sendo estes avaliados quanto às suas características tecnológicas: volume específico, firmeza do miolo e cor da crosta e do miolo. O pão que apresentou as melhores características tecnológicas foi caracterizado quanto à sua composição química (proteínas, lipídios, cinzas, umidade e carboidratos, avaliado quanto às perdas decorrentes da cocção e submetido à análise sensorial. As massas cruas dos pães adicionados com o colágeno em fibra, assim como a massa do pão padrão (sem adição de colágeno, foram avaliadas através de reologia e microscopia eletrônica de varredura. A adição de colágeno aos pães elaborados com farinha de arroz não colaborou para a formação de uma rede semelhante à formada pelo glúten. O pão da formulação com 4% de colágeno em fibra apresentou as características tecnológicas mais próximas ao esperado, não diferindo significativamente quanto à composição química, do pão padrão. Por meio da análise sensorial, constatou-se que os pães sem glúten (padrão e com 4% de colágeno em fibra obtiveram aceitação sensorial superior a 75%. Conclui-se, com o estudo, que é possível adicionar colágeno em pães sem glúten, sendo que o pão adicionado de 4% de colágeno em fibra apresentou características mais próximas às do pão padrão testado.
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Generación de modelos 3D a partir de imágenes SEM (Scanning Electron Microscopy)
MÍNGUEZ HERNÁNDEZ, MARÍA TERESA
2017-01-01
[ES] Con la realización del presente trabajo, se pretenden obtener Modelos Digitales 3D (MD-3D) de imágenes de muy alta resolución obtenidas con un Microscopio Electrónico de Barrido (SEM), utilizando la técnica fotogramétrica Structure from Motion (SfM) mediante el software Agisoft-PhotoScan. El objetivo es comprobar si este tipo de software, que utiliza la técnica SfM, es apto para imágenes obtenidas con equipos SEM y generar Modelos 3D. Esto permitiría poder realizar impr...
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Is scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDS) quantitative?
Newbury, Dale E; Ritchie, Nicholas W M
2013-01-01
Scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDS) is a widely applied elemental microanalysis method capable of identifying and quantifying all elements in the periodic table except H, He, and Li. By following the "k-ratio" (unknown/standard) measurement protocol development for electron-excited wavelength dispersive spectrometry (WDS), SEM/EDS can achieve accuracy and precision equivalent to WDS and at substantially lower electron dose, even when severe X-ray peak overlaps occur, provided sufficient counts are recorded. Achieving this level of performance is now much more practical with the advent of the high-throughput silicon drift detector energy dispersive X-ray spectrometer (SDD-EDS). However, three measurement issues continue to diminish the impact of SEM/EDS: (1) In the qualitative analysis (i.e., element identification) that must precede quantitative analysis, at least some current and many legacy software systems are vulnerable to occasional misidentification of major constituent peaks, with the frequency of misidentifications rising significantly for minor and trace constituents. (2) The use of standardless analysis, which is subject to much broader systematic errors, leads to quantitative results that, while useful, do not have sufficient accuracy to solve critical problems, e.g. determining the formula of a compound. (3) EDS spectrometers have such a large volume of acceptance that apparently credible spectra can be obtained from specimens with complex topography that introduce uncontrolled geometric factors that modify X-ray generation and propagation, resulting in very large systematic errors, often a factor of ten or more. © Wiley Periodicals, Inc.
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Sparsity-Based Super Resolution for SEM Images.
Tsiper, Shahar; Dicker, Or; Kaizerman, Idan; Zohar, Zeev; Segev, Mordechai; Eldar, Yonina C
2017-09-13
The scanning electron microscope (SEM) is an electron microscope that produces an image of a sample by scanning it with a focused beam of electrons. The electrons interact with the atoms in the sample, which emit secondary electrons that contain information about the surface topography and composition. The sample is scanned by the electron beam point by point, until an image of the surface is formed. Since its invention in 1942, the capabilities of SEMs have become paramount in the discovery and understanding of the nanometer world, and today it is extensively used for both research and in industry. In principle, SEMs can achieve resolution better than one nanometer. However, for many applications, working at subnanometer resolution implies an exceedingly large number of scanning points. For exactly this reason, the SEM diagnostics of microelectronic chips is performed either at high resolution (HR) over a small area or at low resolution (LR) while capturing a larger portion of the chip. Here, we employ sparse coding and dictionary learning to algorithmically enhance low-resolution SEM images of microelectronic chips-up to the level of the HR images acquired by slow SEM scans, while considerably reducing the noise. Our methodology consists of two steps: an offline stage of learning a joint dictionary from a sequence of LR and HR images of the same region in the chip, followed by a fast-online super-resolution step where the resolution of a new LR image is enhanced. We provide several examples with typical chips used in the microelectronics industry, as well as a statistical study on arbitrary images with characteristic structural features. Conceptually, our method works well when the images have similar characteristics, as microelectronics chips do. This work demonstrates that employing sparsity concepts can greatly improve the performance of SEM, thereby considerably increasing the scanning throughput without compromising on analysis quality and resolution.
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International Nuclear Information System (INIS)
Joy, D. C.; Newbury, D. E.
1998-01-01
The scanning electron microscope (SEM) represents the most promising tool for metrology, defect review, and for the analysis of ULSI structures, but both fundamental problems such as electron-solid interactions, and practical considerations such as electron-optical constraints, are now setting a limit to performance. This paper examines the directions in which an advanced SEM might be developed to overcome these constraints. The SEM also offers considerable promise as a tool for the high spatial resolution X-ray microanalysis, especially for those situations where a thin cross-section is not practical and first surface analysis is required. The ways in which this capability can be incorporated in an advanced SEM are examined
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International Nuclear Information System (INIS)
Joy, D.C.; Newbury, D.E.; Newbury, D.E.
1998-01-01
The scanning electron microscope (SEM) represents the most promising tool for metrology, defect review, and for the analysis of ULSI structures, but both fundamental problems such as electron-solid interactions, and practical considerations such as electron-optical constraints, are now setting a limit to performance. This paper examines the directions in which an advanced SEM might be developed to overcome these constraints. The SEM also offers considerable promise as a tool for the high spatial resolution X-ray microanalysis, especially for those situations where a thin cross-section is not practical and first surface analysis is required. The ways in which this capability can be incorporated in an advanced SEM are examined. copyright 1998 American Institute of Physics
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SEM analysis for irradiated materials
International Nuclear Information System (INIS)
Liu Xiaosong; Yao Liang
2008-06-01
A radiation-proof Scanning Electron Microscope (SEM) system is introduced. It has been widely used in various areas. For analyzing radioactive samples, normal SEM system needs lots of alterations. Based on KYKY-2800B SEM, the sample room, belt line, operating table and aerator were updated. New radiation-proof SEM system has used to analytic surface contaminated samples and RPV materials samples. An elementary means of SEM analysis for radioactive samples was studied, and this examination supported some available references for further irradiated fuel researches. (authors)
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Directory of Open Access Journals (Sweden)
Costa Aurélio Antônio Ribeiro
2003-01-01
Full Text Available OBJETIVO: comparar os resultados intra e pós-operatórios em pacientes sem prolapso genital ou doenças anexiais, submetidas a histerectomia vaginal ou abdominal. MÉTODOS: realizou-se estudo do tipo ensaio clínico aberto, randomizado, em pacientes sem prolapso genital que se submeteram a histerectomia total, indicada por doenças benignas, no IMIP, em Recife, Pernambuco. Incluíram-se 35 pacientes, alocadas aleatoriamente em dois grupos, sendo 19 submetidas a histerectomia vaginal e 16 a histerectomia abdominal. Foram estudadas as seguintes variáveis: volume de perda sangüínea, necessidade de hemotransfusão, tempo operatório, dor pós-operatória (intensidade e uso de analgésicos, tempo de permanência hospitalar, complicações operatórias, tempo de retorno às atividades e grau de satisfação das pacientes. Para análise estatística, utilizaram-se os testes chi2 de associação, exato de Fisher e Mann-Whitney para comparação dos grupos, considerando-se significativo erro alfa menor que 5%. RESULTADOS: o volume de sangue perdido durante as histerectomias por via abdominal (mediana de 902 mL foi significativamente maior em relação à perda durante as histerectomias vaginais (mediana de 520 mL, e nenhuma paciente neste último grupo requereu hemotransfusão, contra 19% no primeiro grupo. A duração da cirurgia foi semelhante, com mediana de 120 minutos nos dois grupos. A intensidade da dor, verificada pelos escores da escala analógica visual, foi significativamente menor entre as pacientes submetidas a histerectomia vaginal, que também apresentaram menor freqüência de utilização de analgésicos. Não houve diferença na freqüência de complicações intra ou pós-operatórias entre os dois grupos, encontrando-se apenas um caso de infecção em cada grupo e um caso de trombose venosa profunda no grupo das histerectomias vaginais. O tempo de retorno às atividades das pacientes submetidas à histerectomia vaginal foi
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Blancett, Candace D; Fetterer, David P; Koistinen, Keith A; Morazzani, Elaine M; Monninger, Mitchell K; Piper, Ashley E; Kuehl, Kathleen A; Kearney, Brian J; Norris, Sarah L; Rossi, Cynthia A; Glass, Pamela J; Sun, Mei G
2017-10-01
A method for accurate quantitation of virus particles has long been sought, but a perfect method still eludes the scientific community. Electron Microscopy (EM) quantitation is a valuable technique because it provides direct morphology information and counts of all viral particles, whether or not they are infectious. In the past, EM negative stain quantitation methods have been cited as inaccurate, non-reproducible, and with detection limits that were too high to be useful. To improve accuracy and reproducibility, we have developed a method termed Scanning Transmission Electron Microscopy - Virus Quantitation (STEM-VQ), which simplifies sample preparation and uses a high throughput STEM detector in a Scanning Electron Microscope (SEM) coupled with commercially available software. In this paper, we demonstrate STEM-VQ with an alphavirus stock preparation to present the method's accuracy and reproducibility, including a comparison of STEM-VQ to viral plaque assay and the ViroCyt Virus Counter. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
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Percepção de autoinstilação de gotas oculares em idosos com ou sem dispositivo de apoio facial
Directory of Open Access Journals (Sweden)
Arlindo Jose Freire Portes
Full Text Available RESUMO Objetivo: Determinar o grau de dificuldade para instilação tópica ocular em idosos, com ou sem o auxílio de dispositivo de apoio facial, por meio de questionário. Observar qual método foi tecnicamente melhor para aplicação tópica ocular de gotas. Métodos: O estudo foi um ensaio clínico, controlado, randomizado e pareado, realizado em 50 pacientes idosos de setembro de 2015 a junho de 2016 na Policlínica Ronaldo Gazolla, Lapa-Rio de Janeiro. Um frasco de colírio Optive® foi acoplado ao dispositivo de apoio facial denominado Eyedrop®. Cada participante instilou o colírio com ou sem o auxílio do dispositivo em cada um dos olhos, sendo que a seleção ocular foi feita aleatoriamente. Foi perguntado ao paciente questões pré-formuladas sobre a dificuldade de ambos os métodos e a técnica de administração tópica ocular foi avaliada. Resultados: A instilação de gotas foi considerada difícil ou muito difícil por 10% dos idosos com o auxílio do dispositivo e por 36% sem o auxílio (p = 0,0047. Houve toque da ponta do colírio com os tecidos oculares em 64% dos pacientes que não usaram o Eyedrop® e em 4% dos que o utilizaram (p=0,000001. A maior dificuldade descrita na instilação tradicional foi acertar o olho com a gota (32% e com o dispositivo de apoio foi entender seu uso(4%. Conclusão: A maioria dos idosos instila colírios erroneamente, tocando a ponta do frasco em tecidos oculares, o que favorece sua contaminação. O dispositivo de apoio facial tornou mais segura e fácil a instilação.
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Um estudo semântico enunciativo da corrupção em dicionários e documentos governamentais
Directory of Open Access Journals (Sweden)
Julio Cesar Machado
2010-07-01
Full Text Available
Descolamos sentidos da palavra corrupção, seu funcionamento e circulação, privilegiadamente no espaço enunciativo jurídico. Abordamo-la como acontecimento, sob o foco da linguística enunciativo-discursiva, envolvendo questões de ordem histórica, política e social. A pertinência da pesquisa parte do fato de que já são aceitos (pelo povo ou pelo Estado sentidos “não criminais” para o termo. Eles não mais condizem com a memória de desprezível, evidenciado sobremaneira no caso “mensalão”, demonstrando a não transparência da língua, a sua plasticidade polissêmica, a sua constituição política, a sua configuração opaca, bem como seu equívoco indissociável do acontecimento. Mobilizamos para esta visualização, o dispositivo teórico da Semântica do Acontecimento, ancilar à Semântica Histórica da Enunciação e à Analise de Discurso francesa. Tal postura determina a articulação entre teoria e <em>corpus> por meio do <em>a prioriem> da história. Nosso procedimento evidenciará uma língua erudita que pode designar a palavra “corrupção” a partir de seu funcionamento, que se pauta no rol das leis jurídicas e desvela uma performatividade.
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Directory of Open Access Journals (Sweden)
Corazza Vera Regina
2004-01-01
Full Text Available Os grandes avanços na compreensão da fisiologia vocal e o desenvolvimento científico e tecnológico na área de voz permitiram transpor o limite terapêutico através dos meios para a detecção precoce de alterações vocais. OBJETIVO: Avaliar indivíduos sem queixa vocal e correlacionar possíveis achados telelaringo-estroboscópicos, perceptivo-auditivos e acústicos. FORMA DE ESTUDO: Observacional coorte com corte transversal. CASUÍSTICA E MÉTODO: Foram avaliados 21 indivíduos do sexo masculino, com idade variando de 20 a 50 e mediana de 33 anos, sem queixas vocais, que não faziam uso de tabaco nem de destilados. Os sujeitos foram submetidos às avaliações telelaringo-estroboscópica, perceptivo-auditiva e acústica da voz. RESULTADOS: Do total de sujeitos avaliados, 57,15% apresentaram alteração em uma ou mais das avaliações realizadas. À telelaringo-estroboscopia, observou-se fenda vocal triangular posterior em 4 sujeitos. Dez apresentaram alteração na análise perceptivo-auditiva, observando-se os seguintes parâmetros: instabilidade, rouquidão e soprosidade, todos em grau discreto. Na avaliação da ressonância, três apresentaram cada foco hipernasal, cul de sac e laringo-faríngea. A avaliação acústica apresentou as seguintes médias: f0 - 125,69 Hz; jitter - 0,22%; shimmer - 3,06%; NNE -12,29 dB; HNR - 20,75 dB; freqüência do tremor - 2,09 Hz; amplitude do tremor - 1,16 Hz. Alguns sujeitos apresentaram valores de shimmer% e freqüência do tremor maiores do que a média. CONCLUSÃO: Foram detectadas alterações em 57,15% das avaliações realizadas em indivíduos sem queixas vocais. Esses achados podem ser indicativos de uma variação da normalidade ou representar uma predisposição a alterações glóticas e vocais que, com o passar do tempo, podem desenvolver-se. Em todas as avaliações alteradas houve alteração de parâmetro acústico.
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Pendleton, Michael W; Washburn, Dorothy K; Ellis, E Ann; Pendleton, Bonnie B
2014-03-01
The same sherd was analyzed using a scanning electron microscope with energy dispersive spectroscopy (SEM-EDS) and a micro X-ray fluorescence tube attached to a scanning electron microscope (Micro-XRF-SEM) to compare the effectiveness of elemental detection of iron-based pigment. To enhance SEM-EDS mapping, the sherd was carbon coated. The carbon coating was not required to produce Micro-XRF-SEM maps but was applied to maintain an unbiased comparison between the systems. The Micro-XRF-SEM analysis was capable of lower limits of detection than that of the SEM-EDS system, and therefore the Micro-XRF-SEM system could produce elemental maps of elements not easily detected by SEM-EDS mapping systems. Because SEM-EDS and Micro-XRF-SEM have been used for imaging and chemical analysis of biological samples, this comparison of the detection systems should be useful to biologists, especially those involved in bone or tooth (hard tissue) analysis.
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Adapted methods for scanning electron microscopy (SEM in assessment of human sperm morphology
Directory of Open Access Journals (Sweden)
Petra Nussdorfer
2018-02-01
Full Text Available Infertility is a widespread problem, and in some cases, the routine basic semen analysis is not sufficient to detect the cause of male infertility. The use of the scanning electron microscope (SEM could provide a detailed insight into spermatozoa morphology, but it requires specific sample preparation techniques. The purpose of this study was to select, adjust, and optimize a method for the preparation of spermatozoa samples prior to SEM analysis, and to establish the protocol required for its use in clinical practice. We examined sperm samples of 50 men. The samples were fixed with modified iso-osmolar aldehyde solution followed by osmium post-fixation. In the first method, dehydration of the cells and subsequent critical point drying (CPD were performed on a coverslip. In the second method, the samples were dehydrated in centrifuge tubes; hexamethyldisilazane (HMDS was used as a drying agent instead of CPD, and the samples were air-dried. The third procedure was based on a membrane filter. The samples were dehydrated and dried with HMDS in a Gooch crucible, continuously, without centrifugation or redispersion of the sample. Our results showed that the fixation with modified iso-osmolar aldehyde solution followed by osmium post-fixation, and combined with dehydration and CPD on a coverslip, is the most convenient procedure for SEM sample preparation. In the case of small-size samples or low sperm concentration, dehydration and drying with HMDS on the membrane filter enabled the best reliability, repeatability, and comparability of the results. The presented procedures are suitable for routine use, and they can be applied to confirm as well as to correct a diagnosis.
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Special raster scanning for reduction of charging effects in scanning electron microscopy.
Suzuki, Kazuhiko; Oho, Eisaku
2014-01-01
A special raster scanning (SRS) method for reduction of charging effects is developed for the field of SEM. Both a conventional fast scan (horizontal direction) and an unusual scan (vertical direction) are adopted for acquiring raw data consisting of many sub-images. These data are converted to a proper SEM image using digital image processing techniques. About sharpness of the image and reduction of charging effects, the SRS is compared with the conventional fast scan (with frame-averaging) and the conventional slow scan. Experimental results show the effectiveness of SRS images. By a successful combination of the proposed scanning method and low accelerating voltage (LV)-SEMs, it is expected that higher-quality SEM images can be more easily acquired by the considerable reduction of charging effects, while maintaining the resolution. © 2013 Wiley Periodicals, Inc.
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Morfologia dos tricomas em Tibouchina sect. Pleroma (D. Don cogn. (melastomataceae
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Paulo José Fernandes Guimarães
1999-01-01
Full Text Available Melastomataceae é a família que apresenta a maior diversidade de tricomas. Dr. Wurdack em seu "Atlas of hairs" reconheceu 46 tipos de tricomas para as Melastomataceae neotropicais com o uso de MEV, e referiu 17 destes para o gênero Tibouchina. Em Melastomataceae a morfologia dos tricomas tem sido extensivamente usada na delimitação dos táxons, assim como em estudos que antecederam ao trabalho de Cogniaux, a monografia das Melastomataceae brasileiras publicada em 1885. Em Tibouchina sect. Pleroma a morfologia dos tricomas foi substancial para a circunscrição de várias espécies. O uso da MEV permitiu uma caracterização dos 15 tipos diferentes de tricomas observados nas 41 espécies examinadas. Os diferentes tipos são descritos com base no aspecto morfológico tanto em MO como em MEV e ilustrados através de eletromicrografias de varredura e fotomicrografias.The Melastomataceae display greater trichome diversity. Dr. Wurdack, in his Atlas of hairs, recognized 46 types of trichomes for the Neotropical Melastomataceae through the Scanning Electron Microscope (SEM, and referred 17 of them to the genus Tibouchina. The trichome morphology has been extensively used in the delimitation of the taxa in Melastomataceae, as well as in previous studies by Cogniaux, the monograph of Brazilian Melastomataceae published in 1885. The morphology of the trichomes was essential for the delimitation of several species in Tibouchina section Pleroma. The use of SEM provided the best characterization of the 15 different types of trichomes recognized among the 41 species examined. These were described based on the morphological appearance, both optical microscopy and scanning electron microscopy, and illustrated by scanning electron micrographs and photomicrographs.
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Critical factors in SEM 3D stereo microscopy
DEFF Research Database (Denmark)
Marinello, F.; Bariano, P.; Savio, E.
2008-01-01
This work addresses dimensional measurements performed with the scanning electron microscope (SEM) using 3D reconstruction of surface topography through stereo-photogrammetry. The paper presents both theoretical and experimental investigations, on the effects of instrumental variables and measure......This work addresses dimensional measurements performed with the scanning electron microscope (SEM) using 3D reconstruction of surface topography through stereo-photogrammetry. The paper presents both theoretical and experimental investigations, on the effects of instrumental variables...... factors are recognized: the first one is related to the measurement operation and the instrument set-up; the second concerns the quality of scanned images and represents the major criticality in the application of SEMs for 3D characterizations....
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Directory of Open Access Journals (Sweden)
Jagbir Singh Kirti
2014-12-01
Full Text Available Anopheles (Cellia stephensi Liston is a major vector species of malaria in Indian subcontinent. Taxonomists have worked on its various morphological aspects and immature stages to explore additional and new taxonomic attributes. Scanning electron microscopic (SEM studies have been conducted on the fourth instar larva and pupa of An. stephensi to find additional taxonomic features for the first time from Punjab state.
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Directory of Open Access Journals (Sweden)
Roger Keller Celeste
2014-03-01
Full Text Available O objetivo foi descrever a produção de serviços especializados em municípios brasileiros com e sem Centros de Especialidades Odontológicas (CEO e estudar fatores associados. Para a coleta de dados, foram consultados: o Departamento de Informática do SUS, dados do Atlas de Desenvolvimento Humano do Brasil e do Instituto Brasileiro de Geografia e Estatística. Utilizou-se regressão binominal negativa inflada de zeros para modelar taxas de procedimentos de endodontia, atenção básica, periodontia e cirurgia. Após controle por fatores sociodemográficos, os municípios com CEO apresentaram taxas maiores do que os sem, exceto para taxas de atenção básica. No modelo final, com variáveis de estrutura dos serviços, os municípios com CEO do tipo III tiveram uma taxa de procedimentos de endodontia 2,08 (IC95%: 1,26; 3,44 vezes maior que sem CEO. Das variáveis de estrutura, mais gastos em saúde e maiores taxas de dentistas no SUS estavam consistentemente associados a maiores taxas de quaisquer procedimentos. Os CEO parecem ter um efeito positivo na produção municipal de procedimentos especializados, particularmente para a taxa de procedimentos de endodontia, e esse efeito não é explicado por variáveis de estrutura.
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International Nuclear Information System (INIS)
Konoto, Makoto
2007-01-01
Development of highly effective evaluation technology of magnetic structures on a nanometric scale is a key to understanding spintronics and related phenomena. A high-resolution spin-polarized scanning electron microscope (spin SEM) developed recently is quite suitable for probing such nanostructures because of the capability of analyzing local magnetization vectors in three dimensions. Utilizing the spin SEM, a layered antiferromagnetic structure with the 1nm-alternation of bilayer-sheet magnetization has been successfully resolved. The real-space imaging with full analysis of the temperature-dependent magnetization vectors will be demonstrated. (author)
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Directory of Open Access Journals (Sweden)
Glaydson Teixeira Oliveira
2016-06-01
Full Text Available A panbronquiolite difusa é uma doença inflamatória, crônica e idiopática dos bronquíolos respiratórios, raramente observada em ocidentais sem ascendência asiática. O achado histopatológico principal é o acúmulo de macrófagos xantomatosos nas paredes dos bronquíolos respiratórios e a apresentação radiológica típica é o padrão de “árvore em brotamento”, difuso. Descreve-se um incomum caso da doença em uma paciente de 21 anos, natural de Quixadá no Ceará, sem ascendência asiática ou histórico de viagem para países endêmicos. Em áreas não endêmicas e em casos com apresentação clínica, radiológica e laboratorial atípicas, o diagnóstico pode se tornar muito desafiador, especialmente tendo em vista a elevada prevalência de doenças das vias aéreas associadas à bronquiolite e bronquiectasias.
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Edmunson, J.; Gaskin, J. A.; Doloboff, I. J.; Jerman, G.
2017-01-01
Development of a miniaturized scanning electron microscope that will utilize the martian atmosphere to dissipate charge during analysis continues. This instrument is expected to be used on a future rover or lander to answer fundamental Mars science questions. To identify the most important questions, a survey was taken at the 47th Lunar and Planetary Science Conference (LPSC). From the gathered information initial topics were identified for a SEM on the martian surface. These priorities are identified and discussed below. Additionally, a concept of operations is provided with the goal of maximizing the science obtained with the minimum amount of communication with the instrument.
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Directory of Open Access Journals (Sweden)
Francisco Rüdiger
2014-07-01
Full Text Available Questiona-se no texto se uma abordagem que, no essencial, relata a trajetória do chamado ciberativismo de acordo com seus próprios termos se justifica academicamente ou, em vez disso, se mantém prisioneira de uma mitologia que o fenômeno, em si mesmo, já construiu e, por isso, autoriza seus sujeitos a dispensarem sem prejuízo eventual contribuição de origem universitária.
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Directory of Open Access Journals (Sweden)
Silvana Schwab Nascimento
2014-06-01
Full Text Available O objetivo deste artigo é mostrar como a Semântica é representada em dois dicionários referência em estudos linguísticos, a saber, Dicionário das Ciências da Linguagem (1972, de Ducrot & Todorov, e Dicionário de Linguística (1998, de Dubois et al.; e em dois manuais de introdução à linguística, quais sejam, Introdução à Linguística, organizado por Mussalim & Bentes (2001, e Introdução à Linguística, organizado por Fiorin (2007. Com esta proposta, pretendemos definir o que se apresenta como Semântica em obras que frequentemente são indicadas em programas de Cursos de Graduação em Letras e fomentar no leitor alguns questionamentos que circundam uma área do saber a qual enfoca o significado como umas das questões-chave em suas discussões. Por fim, ao apresentarmos a representação de semântica nas obras mencionadas, pretendemos compreender o lugar dos estudos da significação nas ciências da linguagem.
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Brotação e fertilidade de gemas em uvas sem sementes no Vale do São Francisco
Directory of Open Access Journals (Sweden)
Leão Patrícia Coelho de Souza
2003-01-01
Full Text Available Com o objetivo de avaliar a porcentagem de brotação e índice de fertilidade de gemas de cinco variedades de uvas sem sementes em cinco diferentes datas de poda, realizou-se um experimento no Campo Experimental de Bebedouro, da Embrapa Semi-Árido, em Petrolina-PE. O delineamento experimental foi em parcelas subdivididas, constituídas por cinco variedades de uvas sem sementes como tratamentos principais e cinco diferentes épocas de poda como tratamentos secundários, utilizando-se dez repetições constituídas por uma planta. As variedades utilizadas foram Perlette, Thompson Seedless, Marroo Seedless, Catalunha e Superior Seedless, e as épocas de poda foram: 18 e 19/12/2000; 18 a 21/06/2001; 23 a 29/10/2001; 29/01 a 05/02/2002 e 08 a 12/04/2002. As variáveis estudadas foram a porcentagem de brotação e o índice de fertilidade real das gemas determinado pela razão número de cachos por número de gemas. A fertilidade real de gemas foi analisada entre a 1ª e 10ª gema da vara. Os maiores valores médios para brotação e fertilidade foram observados nas variedades Marroo Seedless e Perlette, sendo que as podas realizadas nos meses de junho de 2001 e abril de 2002 favoreceram o aumento da brotação e da fertilidade das gemas na maioria das variedades.
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Avaliação da população de nematóides em bananal com e sem o uso de organomineral
Directory of Open Access Journals (Sweden)
Cecília Helena Silvino Prata Ritzinger
2011-12-01
Full Text Available Com a demanda pela produção integrada, o monitoramento torna-se fundamental para reduzir ou substituir insumos poluentes na fertilização e no manejo de pragas. Muitos produtos têm sido aplicados em áreas de produção, sem o devido registro ou conhecimento de sua eficiência ou de seu efeito sobre pragas e inimigos naturais. Nesta região, o uso de organomineral é preconizado como alternativa ao uso de fertilizante e possivelmente com efeito nematicida. As avaliações, para verificar o efeito deste produto, foram realizadas, por meio de cinco coletas, no período de 2008 a 2010, em três propriedades, em bananais, cv. 'Williams', introduzidos há oito e 13 anos, dentro do projeto de Irrigação de Formoso, em Bom Jesus da Lapa-BA. Foram coletadas dez amostras compostas de duas subamostras de solo e raízes, em área com e sem a aplicação de organomineral. As propriedades, três, foram denominadas, área 1, 2 e 3. A analise de variância foi feita considerando: três épocas de avaliação, dois tratamentos (com e sem organomineral e três propriedades. O nível de dano foi determinado por meio de escala visual e os dados submetidos à ANOVA. Houve interação significativa entre populações de nematoide no ano e propriedade e entre organomineral e propriedade (P<0,01. Não houve correlação entre nível de dano e organomineral nas áreas 1 e 3. Contudo, houve correlação negativa entre o nível de dano e nematoides na presença de organomineral, na área 3 (P<0,01. Meloidogyne spp. foram as espécies que ocorreram em maior população em Bom Jesus da Lapa-BA. A utilização do organomineral não proporcionou redução significativa na população de nematoides. O nível de dano foi baixo, não podendo ser explicado pelo uso do organomineral. O manejo cultural interferiu no desenvolvimento da população de fitonematoides e de nematoides de vida livre.
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International Nuclear Information System (INIS)
Stokes, D J; Morrissey, F; Lich, B H
2006-01-01
Over the last decade techniques such as confocal light microscopy, in combination with fluorescent labelling, have helped biologists and life scientists to study biological architectures at tissue and cell level in great detail. Meanwhile, obtaining information at very small length scales is possible with the combination of sample preparation techniques and transmission electron microscopy (TEM) or scanning transmission electron microscopy (STEM). Scanning electron microscopy (SEM) is well known for the determination of surface characteristics and morphology. However, the desire to understand the three dimensional relationships of meso-scale hierarchies has led to the development of advanced microscopy techniques, to give a further complementary approach. A focused ion beam (FIB) can be used as a nano-scalpel and hence allows us to reveal internal microstructure in a site-specific manner. Whilst FIB instruments have been used to study and verify the three-dimensional architecture of man made materials, SEM and FIB technologies have now been brought together in a single instrument representing a powerful combination for the study of biological specimens and soft materials. We demonstrate the use of FIB SEM to study three-dimensional relationships for a range of length scales and materials, from small-scale cellular structures to the larger scale interactions between biomedical materials and tissues. FIB cutting of heterogeneous mixtures of hard and soft materials, resulting in a uniform cross-section, has proved to be of particular value since classical preparation methods tend to introduce artefacts. Furthermore, by appropriate selection, we can sequentially cross-section to create a series of 'slices' at specific intervals. 3D reconstruction software can then be used to volume-render information from the 2D slices, enabling us to immediately see the spatial relationships between microstructural components
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An electron moiré method for a common SEM
Institute of Scientific and Technical Information of China (English)
Y.M.Xing; S.Kishimoto; Y.R.Zhao
2006-01-01
In the electron moiré method,a high-frequency grating is used to measure microscopic deformation,which promises significant potential applications for the method in the microscopic analysis of materials.However,a special beam scanning control device is required to produce a grating and generate a moiré fringe pattern for the scanning electron microscope (SEM).Because only a few SEMs used in the material science studies are equipped with this device,the use of the electron moiré method is limited.In this study,an electron moiré method for a common SEM without the beam control device is presented.A grating based on a multi-scanning concept is fabricated in any observing mode.A real-time moiré pattern can also be generated in the SEM or an optical filtering system.Without the beam control device being a prerequisite,the electron moiré method can be more widely used.The experimental results from three different types of SEMS show that high quality gratings with uniform lines and less pitch error can be fabricated by this method,and moiré patterns can also be correctly generated.
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International Nuclear Information System (INIS)
Makita, T.; Hatsuoka, M.; Sugi, Y.
1983-01-01
Secretion granules in the shell gland, isthmus, and albumin-secreting region of the hen oviduct were analyzed with WET-scanning electron microscopy (SEM) and EDX, a combination of wide-angle backscattered electron detector (BED) and energy-dispersive X-ray microanalyzer (EDX). Glutaraldehyde-fixed but unhydrated, unstained, and uncoated samples were analyzed; Ca was localized in all secretion granules in all three sections of the hen oviduct studied
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Carvalho, Carlos Alfredo Lopes de; Souza, Bruno de Almeida; Dias, Carleandro de Souza; Alves, Rogério Marcos de Oliveira; Melo, Alex Fábio de Lima; Soares, Ana Cristina Fermino; Carvalho-Zilse, Gislene Almeida
2011-01-01
Polygyny, characterized by the presence of several egg-laying queens, is considered as a temporary colony status. In stingless bees it is rarely observed. This paper reports the first case of natural polygyny in Melipona scutellaris colony, with five egg-laying queens.Poliginia, caracterizada pela presença de mais de uma rainha poedeira, é considerada como uma condição temporária em colônias. Em abelhas sem ferrão isso é raramente observado. Este artigo registra o primeiro caso de poliginia n...
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Directory of Open Access Journals (Sweden)
Elizabete Silva dos Santos
2013-09-01
Full Text Available FUNDAMENTO: Em Síndrome Coronariana Aguda (SCA sem Supradesnivelamento do segmento ST (SST é importante estimar a probabilidade de eventos adversos. Para esse fim, as diretrizes recomendam modelos de estratificação de risco. O escore de risco Dante Pazzanese (escore DANTE é um modelo simples de estratificação de risco, composto das variáveis: aumento da idade (0 a 9 pontos; antecedente de diabete melito (2 pontos ou acidente vascular encefálico (4 pontos; não uso de inibidor da enzima conversora da angiotensina (1 ponto; elevação da creatinina (0 a 10 pontos; combinação de elevação da troponina e depressão do segmento ST (0 a 4 pontos. OBJETIVO: Validar o escore DANTE em pacientes com SCA sem SST. MÉTODOS: Estudo prospectivo, observacional, com inclusão de 457 pacientes, de setembro de 2009 a outubro de 2010. Os pacientes foram agrupados em: muito baixo, baixo, intermediário e alto risco de acordo com a pontuação do modelo original. A habilidade preditiva do escore foi avaliada pela estatística-C. RESULTADOS: Foram 291 (63,7% homens e a média da idade 62,1 anos (11,04. Dezessete pacientes (3,7% apresentaram o evento de morte ou (reinfarto em 30 dias. Ocorreu aumento progressivo na proporção do evento, com aumento da pontuação: muito baixo risco = 0,0%; baixo risco = 3,9%; risco intermediário = 10,9%; alto risco = 60,0%; p < 0,0001. A estatística-C foi de 0,87 (IC 95% 0,81-0,94; p < 0,0001. CONCLUSÃO: O escore DANTE apresentou excelente habilidade preditiva para ocorrência dos eventos específicos e pode ser incorporado na avaliação prognóstica de pacientes com SCA sem SST.
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Kaboli, S.; Burnley, P. C.
2017-12-01
Imaging and characterization of defects in crystalline materials is of significant importance in various disciplines including geoscience, materials science, and applied physics. Linear defects such as dislocations and planar defects such as twins and stacking faults, strongly influence many of the properties of crystalline materials and also reflect the conditions and degree of deformation. Dislocations have been conventionally imaged in thin foils in a transmission electron microscope (TEM). Since the development of field emission scanning electron microscopes (FE-SEM) with high gun brightness and small spot size, extensive efforts have been dedicated to the imaging and characterization of dislocations in semi-conductors using electron channeling contrast imaging (ECCI) in the SEM. The obvious advantages of using SEM over TEM include easier and non-destructive sample preparation and a large field of view enabling statistical examination of the density and distribution of dislocations and other defects. In this contribution, we extend this technique to geological materials and introduce the Real Space Crystallography methodology for imaging and complete characterization of dislocations based on bend contour contrast obtained by ECCI in FE-SEM. Bend contours map out the distortion in the crystal lattice across a deformed grain. The contrast of dislocations is maximum in the vicinity of bend contours where crystal planes diffract at small and positive deviations from the Bragg positions (as defined by Bragg's law of electron diffraction). Imaging is performed in a commercial FE-SEM equipped with a standard silicon photodiode backscattered (BSE) detector and an electron backscatter diffraction (EBSD) system for crystal orientation measurements. We demonstrate the practice of this technique in characterization of a number of geological materials in particular quartz, forsterite olivine and corundum, experimentally deformed at high pressure-temperature conditions. This
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International Nuclear Information System (INIS)
Anon.
1980-01-01
The principle underlying the design of the scanning electron microscope (SEM), the design and functioning of SEM are described. Its applications in the areas of microcircuitry and materials science are outlined. The development of SEM in India is reviewed. (M.G.B.)
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Protons, ions, electrons and the future of the SEM
International Nuclear Information System (INIS)
Joy, D C
2010-01-01
The Scanning Electron Microscope (SEM) is the most widely used high performance microscope in all fields of science but it is now reaching the theoretical limits of its performance. While advances in sources, optics, and detectors, can result in some improvement in performance the ultimate resolution is limited by fundamental physical constraints. One potential alternative is a scanning microscope utilizing light ions such as H+ and He+ . Such an instrument shares all of the benefits of the conventional SEM but is free from the constraints encountered when using electrons and could significantly extend the scope and success of scanning microscopy.
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Zhang, Ying; Huang, Tao; Jorgens, Danielle M; Nickerson, Andrew; Lin, Li-Jung; Pelz, Joshua; Gray, Joe W; López, Claudia S; Nan, Xiaolin
2017-01-01
Sample preparation is critical to biological electron microscopy (EM), and there have been continuous efforts on optimizing the procedures to best preserve structures of interest in the sample. However, a quantitative characterization of the morphological changes associated with each step in EM sample preparation is currently lacking. Using correlative EM and superresolution microscopy (SRM), we have examined the effects of different drying methods as well as osmium tetroxide (OsO4) post-fixation on cell morphology during scanning electron microscopy (SEM) sample preparation. Here, SRM images of the sample acquired under hydrated conditions were used as a baseline for evaluating morphological changes as the sample went through SEM sample processing. We found that both chemical drying and critical point drying lead to a mild cellular boundary retraction of ~60 nm. Post-fixation by OsO4 causes at least 40 nm additional boundary retraction. We also found that coating coverslips with adhesion molecules such as fibronectin prior to cell plating helps reduce cell distortion from OsO4 post-fixation. These quantitative measurements offer useful information for identifying causes of cell distortions in SEM sample preparation and improving current procedures.
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Mathematical model of the seismic electromagnetic signals (SEMS) in non crystalline substances
Energy Technology Data Exchange (ETDEWEB)
Dennis, L. C. C.; Yahya, N.; Daud, H.; Shafie, A. [Electromagnetic cluster, Universiti Teknologi Petronas, 31750 Tronoh, Perak (Malaysia)
2012-09-26
The mathematical model of seismic electromagnetic waves in non crystalline substances is developed and the solutions are discussed to show the possibility of improving the electromagnetic waves especially the electric field. The shear stress of the medium in fourth order tensor gives the equation of motion. Analytic methods are selected for the solutions written in Hansen vector form. From the simulated SEMS, the frequency of seismic waves has significant effects to the SEMS propagating characteristics. EM waves transform into SEMS or energized seismic waves. Traveling distance increases once the frequency of the seismic waves increases from 100% to 1000%. SEMS with greater seismic frequency will give seismic alike waves but greater energy is embedded by EM waves and hence further distance the waves travel.
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Mathematical model of the seismic electromagnetic signals (SEMS) in non crystalline substances
International Nuclear Information System (INIS)
Dennis, L. C. C.; Yahya, N.; Daud, H.; Shafie, A.
2012-01-01
The mathematical model of seismic electromagnetic waves in non crystalline substances is developed and the solutions are discussed to show the possibility of improving the electromagnetic waves especially the electric field. The shear stress of the medium in fourth order tensor gives the equation of motion. Analytic methods are selected for the solutions written in Hansen vector form. From the simulated SEMS, the frequency of seismic waves has significant effects to the SEMS propagating characteristics. EM waves transform into SEMS or energized seismic waves. Traveling distance increases once the frequency of the seismic waves increases from 100% to 1000%. SEMS with greater seismic frequency will give seismic alike waves but greater energy is embedded by EM waves and hence further distance the waves travel.
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FIB-SEM tomography in biology.
Kizilyaprak, Caroline; Bittermann, Anne Greet; Daraspe, Jean; Humbel, Bruno M
2014-01-01
Three-dimensional information is much easier to understand than a set of two-dimensional images. Therefore a layman is thrilled by the pseudo-3D image taken in a scanning electron microscope (SEM) while, when seeing a transmission electron micrograph, his imagination is challenged. First approaches to gain insight in the third dimension were to make serial microtome sections of a region of interest (ROI) and then building a model of the object. Serial microtome sectioning is a tedious and skill-demanding work and therefore seldom done. In the last two decades with the increase of computer power, sophisticated display options, and the development of new instruments, an SEM with a built-in microtome as well as a focused ion beam scanning electron microscope (FIB-SEM), serial sectioning, and 3D analysis has become far easier and faster.Due to the relief like topology of the microtome trimmed block face of resin-embedded tissue, the ROI can be searched in the secondary electron mode, and at the selected spot, the ROI is prepared with the ion beam for 3D analysis. For FIB-SEM tomography, a thin slice is removed with the ion beam and the newly exposed face is imaged with the electron beam, usually by recording the backscattered electrons. The process, also called "slice and view," is repeated until the desired volume is imaged.As FIB-SEM allows 3D imaging of biological fine structure at high resolution of only small volumes, it is crucial to perform slice and view at carefully selected spots. Finding the region of interest is therefore a prerequisite for meaningful imaging. Thin layer plastification of biofilms offers direct access to the original sample surface and allows the selection of an ROI for site-specific FIB-SEM tomography just by its pronounced topographic features.
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Agency theory in a nonprofit organization Teoria de agência em uma organização sem fins lucrativos
Directory of Open Access Journals (Sweden)
Ivan Luiz Ecco
2010-10-01
Full Text Available The aim of this paper is to analyze, based on the agency theory, the existence of agency conflicts in management by results in a professional education nonprofit organization. For the program, the case study method was used in a nonprofit professional education organization, located in the state of Santa Catarina. The study examined the contract between the Headquarters of the Organization (which represents in this study, according to theory of agency, the principal and its School Units (representing, the agents to accomplish goals. The results show that the asymmetry of information and organizational culture are factors that contribute to the problem of agency and the determination of an optimal contract should take into consideration such situations. The main conclusion is that agency problems are also present in nonprofit organizations, even when an instrument for the management by results is implemented.O objetivo deste artigo é analisar, à luz da teoria da agência, a existência de conflitos de agência, em uma gestão por resultados, de uma organização educacional sem fins lucrativos. Para sua realização utilizou-se o método de estudo de caso em uma organização de educação profissional sem fins lucrativos, situada no Estado de Santa Catarina. O estudo analisou o contrato celebrado entre a Sede da Organização (que representa neste estudo, segundo a teoria da agência, o principal e suas Unidades Escolares (consideradas os agentes para o cumprimento de metas. Os resultados demonstram que a assimetria de informação e a cultura organizacional são fatores quecontribuem para que o problema de agência ocorra e a determinação de um contrato ótimo deveria levar em consideração tais situações. A principal conclusão é de que os problemas de agência também estão presentes nas organizações sem fins lucrativos, mesmo quando se implanta um instrumento para realizar a gestão por resultados.
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O teste de frio sem solo em sementes de abóbora The modified cold germination test in squash seeds
Directory of Open Access Journals (Sweden)
Derblai Casaroli
2006-12-01
Full Text Available Este trabalho teve como objetivo determinar o período de exposição à baixa temperatura no teste de frio sem solo, para avaliação de diferentes potenciais fisiológicos em lotes de sementes de abóbora. Foram avaliados seis lotes de sementes de abóbora cultivar "Menina Brasileira" (Cucurbita moschata Duch. produzidas na safra 2003/2004. As sementes foram submetidas a diferentes períodos (três, cinco, sete e nove dias de exposição à baixa temperatura para condução do teste de frio sem solo, a uma temperatura constante de 10°C. Utilizou-se o delineamento inteiramente casualizado, em que os tratamentos constituíram um fatorial 6x4 (seis lotes e quatro períodos de exposição, com quatro repetições de 50 sementes. As médias foram comparadas pelo teste de Tukey em nível de 5% de probabilidade de erro. Realizou-se também o teste de correlação simples de Pearson .Os resultados permitiram concluir que o período de três dias de exposição à baixa temperatura foi o mais indicado para a condução do teste de frio sem solo em sementes de abóbora.This research was aimed at determining the exposition period at low temperature in the modified cold germination test, to evaluate physiological potential of squash seed lots. Six seed lots of squash, variety Menina Brasileira (Cucurbita moschata Duch., produced in 2003/2004, were submitted at different exposition times for the development of the cold test. The modified cold gernation test was carried out at 10°C of constant temperature, during exposition time of three, five, seven and nine days. A completely randomized desing was used to the cold test, 0 constituting a factorial 6x4, corresponding to the six seed lots and four exposition time (3, 5, 7, and 9 days, with four repetitions. The averages were compared by the Tukey test, at 5% of probability. The correlation test of Person (r was used too. For the modified cold germination test, the period of three days was the most
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Qualidade de framboesas sem cobertura ou cobertas sobre o dossel e em diferentes espaçamentos
Directory of Open Access Journals (Sweden)
Paula Nogueira Curi
2014-03-01
Full Text Available A framboesa é uma pequena fruta de grande importância econômica, que contém numerosos compostos fenólicos, com potenciais benéficos à saúde; porém, quando cultivada em regiões subtropicais, possui problemas com podridões pós-colheita. O objetivo do presente trabalho foi determinar a qualidade de framboesas cultivadas sem cobertura ou com o dossel coberto com cobertura plástica e em diferentes espaçamentos (3 x 0,50 m e 3 x 0,25 m. Foram avaliadas: a coloração dos frutos, a quantidade de antocianinas, vitamina C, cinzas, umidade, sólidos solúveis totais, açúcares, acidez, firmeza, incidência de ferrugem nos frutos e a composição mineral (nitrogênio, fósforo, potássio, cálcio, magnésio, enxofre, boro, cobre, manganês, zinco e ferro. Ao final, observou-se que cultivo com espaçamento 3 x 0,25 m e cobertas com cobertura plástica aumentou a qualidade das framboesas.
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Directory of Open Access Journals (Sweden)
Gilmar Moraes Santos
Full Text Available INTRODUÇÃO: A síndrome de dor femoropatelar (SDFP é um problema comum que afeta uma em cada quatro pessoas. A alteração no tempo de ativação e a intensidade de contração dos músculos vasto medial oblíquo (VMO e vasto lateral (VL são consideradas fatores importantes na etiologia da SDFP. No entanto, existem poucos estudos sobre a função da porção oblíqua do vasto lateral (VLO e nenhum sobre o tempo de ativação (onset do VLO em atividades funcionais em sujeitos normais e com SDFP. OBJETIVO: Assim, o objetivo do estudo foi investigar o tempo de início de atividade eletromiográfica nos músculos VMO, VLO e VL longo (VLL durante a marcha. MATERIAIS E MÉTODOS: A amostra foi formada por 15 sujeitos sem e 12 com SDFP. Dados eletromiográficos foram obtidos dos músculos VMO, VLL e VLO durante caminhada na esteira sem inclinação. A diferença relativa no onset (DRO entre VMO-VLL e VMO-VLO foi determinada a partir da média de três passadas. RESULTADOS: Houve diferença entre os sujeitos com e sem SDFP em relação à DRO entre VMO-VLL. Nos sujeitos com SDFP, a ordem de início da atividade elétrica foi VLL seguida por VLO e após VMO. Nos indivíduos sem a patologia, a ordem foi diferente: primeiro VMO após VLO e, por último, VLL. CONCLUSÃO: Os achados sugerem que a ativação do VMO após o VLL poderia auxiliar no desenvolvimento e na manutenção da SDFP, enquanto o tempo de ativação do VLO possui menor participação.
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Directory of Open Access Journals (Sweden)
Zeni Fonseca Pinto Tomaz
2014-12-01
Full Text Available Uma das carências observadas na cultura do pessegueiro no Brasil é, sem dúvida, a necessidade de novas tecnologias na área de produção de mudas. A qualidade da muda e o tempo para sua formação é a base do pomar e do sucesso da exploração frutícola. A produção de mudas de pessegueiro através da estaquia vem sendo utilizada comercialmente em alguns países, tendo como principais vantagens a facilidade de realização, o baixo custo e a rapidez na produção da muda. Diante do exposto, objetivou-se com o presente estudo avaliar o comportamento da cultivar Maciel enxertada através de gema ativa e gema dormente em porta-enxertos clonados e desenvolvidos em sistema de cultivo sem solo. O trabalho foi conduzido em casa de vegetação e estufa agrícola localizadas no Campo Didático e Experimental do Departamento de Fitotecnia, Faculdade de Agronomia Eliseu Maciel, da Universidade Federal de Pelotas (UFPel/RS, no período de março de 2010 a maio de 2011, e de novembro de 2010 a novembro de 2011. O material vegetal utilizado foram miniestacas de pessegueiro das cultivares Okinawa e Flordaguard e, após, transplantadas para o sistema semi-hidropônico, com diâmetro adequado, foram enxertadas borbulhas de gema ativa e dormente da cultivar Maciel, conforme a época. Nos porta-enxertos 'Okinawa' e 'Flordaguard', o comportamento foi semelhante em relação ao índice de pegamento quando enxertadas borbulhas de 'Maciel' de gema ativa, enquanto com a gema dormente o índice de pegamento foi menor no porta-enxerto 'Okinawa'. As mudas provenientes da enxertia de gema ativa atingiram o comprimento para a muda comercialmente pronta com maior rapidez. As mudas provenientes da enxertia de gema dormente obtiveram maior número de brotações laterais.
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Hamers, Maartje F.; Pennock, Gill M.; Herwegh, Marco; Drury, Martyn R.
2016-10-01
Planar deformation features (PDFs) in quartz are one of the most reliable and most widely used forms of evidence for hypervelocity impact. PDFs can be identified in scanning electron microscope cathodoluminescence (SEM-CL) images, but not all PDFs show the same CL behavior: there are nonluminescent and red luminescent PDFs. This study aims to explain the origin of the different CL emissions in PDFs. Focused ion beam (FIB) thin foils were prepared of specific sample locations selected in composite color SEM-CL images and were analyzed in a transmission electron microscope (TEM). The FIB preparation technique allowed a direct, often one-to-one correlation between the CL images and the defect structure observed in TEM. This correlation shows that composite color SEM-CL imaging allows distinction between amorphous PDFs on one hand and healed PDFs and basal Brazil twins on the other: nonluminescent PDFs are amorphous, while healed PDFs and basal Brazil twins are red luminescent, with a dominant emission peak at 650 nm. We suggest that the red luminescence is the result of preferential beam damage along dislocations, fluid inclusions, and twin boundaries. Furthermore, a high-pressure phase (possibly stishovite) in PDFs can be detected in color SEM-CL images by its blue luminescence.
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Determinação direta das fases na difração de raios-X em cristais sem centro de simetria
Jose Antonio Prado Valladares
1984-01-01
Resumo: Um método experimental é proposto para solucionar o problema da fase na difração de raios-X em cristais sem centro de simetria, usando difração múltipla caso três-feixes tipo-Bragg. Este método resulta da consideração da dependência da fase com a assimetria dos perfis de linha, com o sentido da rotação da rede cristalina e com o comprimento de onda da radiação incidente. Casos em que o comprimento de onda da radiação incidente está acima e abaixo da borda de absorção, lE, do átomo mai...
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Prevalência de zumbido, em idosos com e sem história de exposição ao ruído ocupacional
Melo,Juliana Jandre; Meneses,Caroline Luiz; Marchiori,Luciana Lozza de Moraes
2012-01-01
INTRODUÇÃO: A variedade de alterações metabólicas e circulatórias relacionadas com o ruído pode causar o aparecimento de inúmeros sintomas auditivos, incluindo, zumbido. OBJETIVO: O objetivo do estudo foi avaliar a prevalência de queixa de zumbido, em idosos com e sem história de exposição ao ruído ocupacional. MÉTODO: Forma de estudo prospectivo foi realizado em uma amostra populacional com 502 indivíduos com idade superior a 60 anos, através de questionário padronizado e avaliação audiológi...
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Directory of Open Access Journals (Sweden)
Maucha Andrade Gamonal
2015-12-01
Full Text Available O artigo destaca diretrizes utilizadas para o desenvolvimento do Copa 2014 FrameNet Brasil, dicionário eletrônico multilíngue, Português, Inglês, Espanhol, para os domínios da Copa, do Futebol e do Turismo. Utilizando uma teoria linguística que enfatiza a estreita relação entre sistema linguístico e experiência humana, possibilitada através de corpus, a Semântica de Frames investe, com o termo frame, em modelagens de experiências e eventos humanos que possibilitam atribuir sentidos às palavras. A rede semântica, FrameNet, em constante desenvolvimento para a língua inglesa no International Computer Science Institute, em Berkeley, em processo de extensão para outras línguas em diversos países como o Brasil, fornece a metodologia necessária para a ampliação deste recurso. O produto desenvolvido a partir deste aporte teórico-metodológico, disponível online gratuitamente, é aqui apresentado através do domínio turístico.
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Extracção de relações semânticas. Recursos, ferramentas e estratégias
García González, Marcos
2015-01-01
A extracção de relações, enquadrada dentro das tarefas de extracção de informação, visa obter automaticamente exemplos de relações semânticas presentes em textos. Esta informação pode ser posteriormente organizada em formatos legíveis por computadores, sendo útil para diversas aplicações que necessitem conhecimento semântico estruturado. A presente tese avalia diferentes estratégias para a extracção automática de relações semânticas de textos em português, espanhol e galego. Co...
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SEM probe of IC radiation sensitivity
Gauthier, M. K.; Stanley, A. G.
1979-01-01
Scanning Electron Microscope (SEM) used to irradiate single integrated circuit (IC) subcomponent to test for radiation sensitivity can localize area of IC less than .03 by .03 mm for determination of exact location of radiation sensitive section.
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Oxford CyberSEM: remote microscopy
International Nuclear Information System (INIS)
Rahman, M; Kirkland, A; Cockayne, D; Meyer, R
2008-01-01
The Internet has enabled researchers to communicate over vast geographical distances, sharing ideas and documents. e-Science, underpinned by Grid and Web Services, has enabled electronic communications to the next level where, in addition to document sharing, researchers can increasingly control high precision scientific instruments over the network. The Oxford CyberSEM project developed a simple Java applet via which samples placed in a JEOL 5510LV Scanning Electron Microscope (SEM) can be manipulated and examined collaboratively over the Internet. Designed with schoolchildren in mind, CyberSEM does not require any additional hardware or software other than a generic Java-enabled web browser. This paper reflects on both the technical and social challenges in designing real-time systems for controlling scientific equipments in collaborative environments. Furthermore, it proposes potential deployment beyond the classroom setting.
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Green Biosynthesis of Silver Nanoparticles Using <em>Callicarpa maingayiem> Stem Bark Extraction
Directory of Open Access Journals (Sweden)
Mohammed Zidan
2012-07-01
Full Text Available Different biological methods are gaining recognition for the production of silver nanoparticles (Ag-NPs due to their multiple applications. The use of plants in the green synthesis of nanoparticles emerges as a cost effective and eco-friendly approach. In this study the green biosynthesis of silver nanoparticles using <em>Callicarpa maingayi em>stem bark extract has been reported. Characterizations of nanoparticles were done using different methods, which include; ultraviolet-visible spectroscopy (UV-Vis, powder X-ray diffraction (XRD, transmission electron microscopy (TEM, scanning electron microscopy (SEM, energy dispersive X-ray fluorescence (EDXF spectrometry, zeta potential measurements and Fourier transform infrared (FT-IR spectroscopy. UV-visible spectrum of the aqueous medium containing silver nanoparticles showed absorption peak at around 456 nm. The TEM study showed that mean diameter and standard deviation for the formation of silver nanoparticles were 12.40 ± 3.27 nm. The XRD study showed that the particles are crystalline in nature, with a face centered cubic (fcc structure. The most needed outcome of this work will be the development of value added products from <em>Callicarpa maingayi em>for biomedical and nanotechnology based industries.
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Rodríguez, José-Rodrigo; Turégano-López, Marta; DeFelipe, Javier; Merchán-Pérez, Angel
2018-01-01
Semithin sections are commonly used to examine large areas of tissue with an optical microscope, in order to locate and trim the regions that will later be studied with the electron microscope. Ideally, the observation of semithin sections would be from mesoscopic to nanoscopic scales directly, instead of using light microscopy and then electron microscopy (EM). Here we propose a method that makes it possible to obtain high-resolution scanning EM images of large areas of the brain in the millimeter to nanometer range. Since our method is compatible with light microscopy, it is also feasible to generate hybrid light and electron microscopic maps. Additionally, the same tissue blocks that have been used to obtain semithin sections can later be used, if necessary, for transmission EM, or for focused ion beam milling and scanning electron microscopy (FIB-SEM).
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Directory of Open Access Journals (Sweden)
Lênio Souza Alvarenga
1999-12-01
Full Text Available Objetivo: Estudar a influência do equivalente esférico nos valores obtidos pelo GDX TM Scanning Laser System®. Métodos: Foram avaliados 41 olhos de 41 voluntários sem doenças oculares e com campo visual sem alterações. Foi realizada a polarimetria de varredura a laser com o GDX TM Scanning Laser System® de acordo com as instruções contidas no manual do aparelho. Foram comparados os valores obtidos nesse exame em um grupo de pacientes com equivalente esférico positivo e em um outro com este valor nulo ou negativo, pelo teste de Mann-Whitney. Resultados: Não se verificou diferença estatística entre os valores obtidos nos olhos de pacientes do grupo I e os do grupo II. Não foi encontrada correlação entre o equivalente esférico e os valores obtidos com o GDX TM Scanning Laser System®. Conclusões: Na amostra estudada não houve diferença estatística entre os valores obtidos em um grupo de olhos com equivalente esférico positivo e outro com este valor negativo ou nulo, usando-se o GDX TM Scanning Laser System®.Purpose: To evaluate the effect of spherical equivalent on the acquisition of nerve fiber layer (NFL thickness with GDX TM Scanning Laser System®. Methods: Forty-one eyes of 41 volunteers were enrolled in this study. All of them presented with no ocular disease and no visual field defect. The NFL thickness was measured with GDX TM Scanning Laser System® as described in its manual. The values obtained in a group of volunteers with negative spherical equivalent (group I were compared to those from a group with a positive spherical equivalent (group II by the Mann-Whitney test. Results: There was no statistical difference between mea-surements in eyes of group I and those in group II. The NFL thickness measurements were not correlated with the sphe-rical equivalent. Conclusions: In the studied group there was no statistical difference in the GDX TM Scanning Laser System® parameters related to spherical equivalent.
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Costa, Ana Lúcia de Jesus
2011-01-01
Mestrado em Contabilidade A crescente importância das Organizações Sem Fins Lucrativos (OSFL) na actividade económica das sociedades modernas tem levado a um aumento da procura de informação financeira e não financeira sobre estas entidades. Cada vez mais as OSFL devem dar ênfase à accountability, atendendo às especificidades da sua actividade, de modo a que os seus documentos de prestação de contas garantam uma imagem fidedigna e apropriada do seu desempenho, devendo, portanto, afastar...
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SEM microcharacterization of semiconductors
Holt, D B
1989-01-01
Applications of SEM techniques of microcharacterization have proliferated to cover every type of material and virtually every branch of science and technology. This book emphasizes the fundamental physical principles. The first section deals with the foundation of microcharacterization in electron beam instruments and the second deals with the interpretation of the information obtained in the main operating modes of a scanning electron microscope.
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Scanning tunnel microscope with large vision field compatible with a scanning electron microscope
International Nuclear Information System (INIS)
Volodin, A.P.; Stepanyan, G.A.; Khajkin, M.S.; Ehdel'man, V.S.
1989-01-01
A scanning tunnel microscope (STM) with the 20μm vision field and 1nm resolution, designed to be compatible with a scanning electron microscope (SEM), is described. The sample scanning area is chosen within the 3x10mm limits with a 0.1-1μm step. The STM needle is moved automatically toward the sample surface from the maximum distance of 10mm until the tunneling current appears. Bimorphous elements of the KP-1 piezocorrector are used in the STM design. The device is installed on a table of SEM object holders
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Directory of Open Access Journals (Sweden)
Iara Felicio Anunciato
2013-10-01
Full Text Available FUNDAMENTO: O papel do estresse oxidativo em pacientes idosos hipertensos com síndrome de apneia-hipopneia obstrutiva do sono (SAHOS é desconhecido. Objetivo: O objetivo foi avaliar os níveis de Big Endotelina-1 (Big ET-1 e Óxido Nítrico (NO em pacientes idosos hipertensos com e sem SAHOS moderada a grave. MÉTODOS: Os voluntários permaneceram internados durante 24 horas. Obtivemos os seguintes dados: índice de massa corporal (IMC, Monitorização Ambulatorial da Pressão Arterial (MAPA - 24 horas, e medicação atual. Sangue arterial foi coletado às 7:00 h e às 19:00 h para determinar níveis plasmáticos de NO e Big ET-1. A oximetria de pulso foi realizada durante o sono. A correlação de Pearson, Spearman e análise de variância univariada foram utilizadas para a análise estatística. RESULTADOS: Foram estudados 25 sujeitos com SAHOS (grupo 1 e 12 sem SAHOS (grupo 2, com idades de 67,0 ± 6,5 anos, 67,8 ± 6,8 anos, respectivamente. Não foram observadas diferenças significativas entre os grupos em IMC; no número de horas de sono; PA diastólica e sistólica em 24 h; PA de vigília; PA no sono; ou medicamentos usados para controlar a PA. Não foram detectadas diferenças nos níveis de NO e Big ET-1 plasmáticos às 19:00 h, mas às 7:00 h os níveis de de Big ET-1 foram mais altos (p = 0,03. No grupo 1, correlação negativa também foi observada entre a saturação de oxihemoglobina arterial média e a PA sistólica - 24 horas (p = 0,03, r = -0,44, e Big ET-1 (p = 0,04, r = 0,41. CONCLUSÕES: Na comparação entre idosos hipertensos com e sem SAHOS com PA e IMC semelhantes, observou-se níveis mais elevados de Big ET-1 após o sono no grupo SAHOS. Os níveis de NO não diferiram entre os pacientes hipertensos com ou sem SAHOS.
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Rodríguez-Chávez, Jacqueline Adelina; Arenas-Alatorre, Jesús; Belio-Reyes, Irma Araceli
2017-07-01
Clinical procedures when shear forces are applied to brackets suggest adhesion forces between 2.8 and 10.0 MPa as appropriate. In this study dental enamel was evaluated by scanning electron microscopy (SEM) before and after removing the brackets. Thirty bicuspids (previous prophylaxis) with metallic brackets (Roth Inovation 0.022 GAC), Transbond Plus SEP 3M Unitek adhesive and Transbond XT 3M resin were used. The samples were preserved to 37°C during 24 hr and submited to tangential forces with the Instron Universal machine 1.0 mm/min speed load strength resistance debonding. Also the Adhesive Remanent Index (ARI) test was made, evaluating the bracket base and the bicuspid surface. All the bracket SEM images were processed with AutoCAD to determine the enamel detached area. The average value was 6.86 MPa (SD ± 3.2 MPa). ARI value 1= 63.3%, value 2= 20%, value 3= 13.3% and 33% presented value 0. All those samples with dental enamel loss, presented different situations as fractures, ledges, horizontal, and vertical loss in some cases, and some scratch lines. There is no association between the debonding resistance and enamel presence. Less than half of the remanent adhesive on the dental enamel was present in most of the samples when the ARI test was applied. When the resin area increases, the debonding resistance also increases, and when the enamel loss increases, the resin free metallic area of the bracket base decreases in the debonding. © 2017 Wiley Periodicals, Inc.
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McBride, E L; Rao, A; Zhang, G; Hoyne, J D; Calco, G N; Kuo, B C; He, Q; Prince, A A; Pokrovskaya, I D; Storrie, B; Sousa, A A; Aronova, M A; Leapman, R D
2018-06-01
Microscopies based on focused electron probes allow the cell biologist to image the 3D ultrastructure of eukaryotic cells and tissues extending over large volumes, thus providing new insight into the relationship between cellular architecture and function of organelles. Here we compare two such techniques: electron tomography in conjunction with axial bright-field scanning transmission electron microscopy (BF-STEM), and serial block face scanning electron microscopy (SBF-SEM). The advantages and limitations of each technique are illustrated by their application to determining the 3D ultrastructure of human blood platelets, by considering specimen geometry, specimen preparation, beam damage and image processing methods. Many features of the complex membranes composing the platelet organelles can be determined from both approaches, although STEM tomography offers a higher ∼3 nm isotropic pixel size, compared with ∼5 nm for SBF-SEM in the plane of the block face and ∼30 nm in the perpendicular direction. In this regard, we demonstrate that STEM tomography is advantageous for visualizing the platelet canalicular system, which consists of an interconnected network of narrow (∼50-100 nm) membranous cisternae. In contrast, SBF-SEM enables visualization of complete platelets, each of which extends ∼2 µm in minimum dimension, whereas BF-STEM tomography can typically only visualize approximately half of the platelet volume due to a rapid non-linear loss of signal in specimens of thickness greater than ∼1.5 µm. We also show that the limitations of each approach can be ameliorated by combining 3D and 2D measurements using a stereological approach. Copyright © 2018. Published by Elsevier Inc.
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DEFF Research Database (Denmark)
Khanmohammadi, Mahdieh; Waagepetersen, Rasmus Plenge; Sporring, Jon
2015-01-01
deviations from spherical shape and systematic trends in their orientation. We studied three-dimensional representations of synapses obtained by manual annotation of focused ion beam scanning electron microscopy (FIB-SEM) images of male mouse brain. The configurations of synaptic vesicles were regarded...... in excitatory synapses appeared to be of oblate ellipsoid shape and in inhibitory synapses appeared to be of cigar ellipsoid shape, and followed a systematic pattern regarding their orientation towards the active zone. Moreover, there was strong evidence of spatial alignment in the orientations of pairs...
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Critical factors in SEM 3D stereo microscopy
International Nuclear Information System (INIS)
Marinello, F; Savio, E; Bariani, P; Horsewell, A; De Chiffre, L
2008-01-01
This work addresses dimensional measurements performed with the scanning electron microscope (SEM) using 3D reconstruction of surface topography through stereo-photogrammetry. The paper presents both theoretical and experimental investigations, on the effects of instrumental variables and measurement parameters on reconstruction accuracy. Investigations were performed on a novel sample, specifically developed and implemented for the tests. The description is based on the model function introduced by Piazzesi and adapted for eucentrically tilted stereopairs. Two main classes of influencing factors are recognized: the first one is related to the measurement operation and the instrument set-up; the second concerns the quality of scanned images and represents the major criticality in the application of SEMs for 3D characterizations
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Ornelas, Fernando César de
2004-01-01
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-graduação em Ciência da Computação Nesta dissertação apresentamos um estudo de caso de aplicação real de rede sem fio, cujo objetivo é a melhoria nas atividades de inspeção e a identificação da necessidade de manutenção em máquinas e equipamentos na área industrial. Fazendo utilização de redes sem fios e de unidades móveis, que se conectam periodicamente a uma rede estruturada, permitimos a...
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Kownacki, Andrzej; Woznicka, Olga; Szarek-Gwiazda, Ewa; Michailova, Paraskeva
2016-09-21
Larvae belonging to the family Chironomidae are difficult to identify. The aim of the present study was to describe the larval morphology of G. (G.) glaucus with the aid of a Scanning Electron Microscope (SEM), the karyotype and biology based on materials obtained from laboratory culture. Describing the morphology of larvae, special attention was paid to rarely or never described structures like the maxilla (lacinia and maxillary palp), the long plate situated below the ventromental plate, and plate X situated between lacinia and mentum. The use of SEM allowed also to obtain better images of labrum and ventromental plate. Morphological features of this species have been supplemented by karyotype and biology of larvae in laboratory conditions. Under controlled experimental conditions we found non-synchronous development of G. (G.) glaucus larvae hatched from one egg mass reflected in different lengths of larvae and emerged imagoes.
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Heitor de Freitas Vieira
2015-01-01
A mitigação de desastres naturais exige respostas rápidas e confiáveis. No Brasil, a estação de chuvas provoca muitos alagamentos em regiões urbanas e, para monitorar esse fenômeno, foi instalada em São Carlos-SP uma rede de sensores sem fio para acompanhar o nível de água dos rios da cidade. Entretanto, essa rede de sensores está suscetível a falhas que podem comprometer o funcionamento do sistema, e a adoção de mecanismos redundantes e de redes móveis 3G podem acarretar em custos proibitivo...
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Meyer, Jörg; Thomas, Christian; Tappe, Frank; Ogbazghi, Tekie
2016-06-16
In failure analysis, device characterization and reverse engineering of light emitting diodes (LEDs), and similar electronic components of micro-characterization, plays an important role. Commonly, different techniques like X-ray computed tomography (CT), light microscopy (LM) and scanning electron microscopy (SEM) are used separately. Similarly, the results have to be treated for each technique independently. Here a comprehensive study is shown which demonstrates the potentials leveraged by linking CT, LM and SEM. In depth characterization is performed on a white emitting LED, which can be operated throughout all characterization steps. Major advantages are: planned preparation of defined cross sections, correlation of optical properties to structural and compositional information, as well as reliable identification of different functional regions. This results from the breadth of information available from identical regions of interest (ROIs): polarization contrast, bright and dark-field LM images, as well as optical images of the LED cross section in operation. This is supplemented by SEM imaging techniques and micro-analysis using energy dispersive X-ray spectroscopy.
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SEM investigation of heart tissue samples
International Nuclear Information System (INIS)
Saunders, R; Amoroso, M
2010-01-01
We used the scanning electron microscope to examine the cardiac tissue of a cow (Bos taurus), a pig (Sus scrofa), and a human (Homo sapiens). 1mm 3 blocks of left ventricular tissue were prepared for SEM scanning by fixing in 96% ethanol followed by critical point drying (cryofixation), then sputter-coating with gold. The typical ridged structure of the myofibrils was observed for all the species. In addition crystal like structures were found in one of the samples of the heart tissue of the pig. These structures were investigated further using an EDVAC x-ray analysis attachment to the SEM. Elemental x-ray analysis showed highest peaks occurred for gold, followed by carbon, oxygen, magnesium and potassium. As the samples were coated with gold for conductivity, this highest peak is expected. Much lower peaks at carbon, oxygen, magnesium and potassium suggest that a cystallized salt such as a carbonate was present in the tissue before sacrifice.
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SEM investigation of heart tissue samples
Energy Technology Data Exchange (ETDEWEB)
Saunders, R; Amoroso, M [Physics Department, University of the West Indies, St. Augustine, Trinidad and Tobago, West Indies (Trinidad and Tobago)
2010-07-01
We used the scanning electron microscope to examine the cardiac tissue of a cow (Bos taurus), a pig (Sus scrofa), and a human (Homo sapiens). 1mm{sup 3} blocks of left ventricular tissue were prepared for SEM scanning by fixing in 96% ethanol followed by critical point drying (cryofixation), then sputter-coating with gold. The typical ridged structure of the myofibrils was observed for all the species. In addition crystal like structures were found in one of the samples of the heart tissue of the pig. These structures were investigated further using an EDVAC x-ray analysis attachment to the SEM. Elemental x-ray analysis showed highest peaks occurred for gold, followed by carbon, oxygen, magnesium and potassium. As the samples were coated with gold for conductivity, this highest peak is expected. Much lower peaks at carbon, oxygen, magnesium and potassium suggest that a cystallized salt such as a carbonate was present in the tissue before sacrifice.
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Directory of Open Access Journals (Sweden)
Carles eBosch
2015-05-01
Full Text Available The fine analysis of synaptic contacts is usually performed using transmission electron microscopy (TEM and its combination with neuronal labeling techniques. However, the complex 3D architecture of neuronal samples calls for their reconstruction from serial sections. Here we show that focused ion beam/scanning electron microscopy (FIB/SEM allows efficient, complete, and automatic 3D reconstruction of identified dendrites, including their spines and synapses, from GFP/DAB-labeled neurons, with a resolution comparable to that of TEM. We applied this technology to analyze the synaptogenesis of labeled adult-generated granule cells (GCs in mice. 3D reconstruction of spines in GCs aged 3–4 and 8–9 weeks revealed two different stages of spine development and unexpected features of synapse formation, including vacant and branched spines and presynaptic terminals establishing synapses with up to 10 spines. Given the reliability, efficiency, and high resolution of FIB/SEM technology and the wide use of DAB in conventional EM, we consider FIB/SEM fundamental for the detailed characterization of identified synaptic contacts in neurons in a high-throughput manner.
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Directory of Open Access Journals (Sweden)
Thais Fernandes Sampaio
2013-01-01
Full Text Available Assumindo a perspectiva da Gramática das Construções Baseada no Uso (GOLDBERG, 1995, 2006; TOMASELLO, 2006, este artigo apresenta e discute um caso de desencontro sintático-semântico em uma Construção de Tópico do Português do Brasil. A Construção de Argumento Cindido com SN-Artefato (Meu tênis descolou o solado; O computador queimou o HD foi inicialmente descrita e analisada em pesquisa que identificou uma Família de Construção de Argumento Cindido no PB (SAMPAIO, 2010. Em uma breve apresentação de nossos pressupostos teóricos, discutimos, especialmente, o conceito de Construção e de Construção de Estrutura Argumental (GOLDBERG, 1995, 2003 e o conceito de desencontro (ou mismatch, nos termos de Francis e Michaelis (2000, Michaelis (2004 e Traugott (2007. A partir da análise de dados de uso, o estudo procura oferecer um tratamento abrangente ao fenômeno, considerando aspectos sintáticos, semânticos e pragmáticos da Construção. A análise identifica, nas instanciações dessa Construção, um desencontro no número de argumentos (um argumento semântico e dois argumentos sintáticos, e confirma a motivação pragmática desta, caracterizando-a como uma Construção de Tópico.
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Directory of Open Access Journals (Sweden)
Thais Fernandes Sampaio
2013-01-01
Full Text Available Assumindo a perspectiva da Gramática das Construções Baseada no Uso (GOLDBERG, 1995, 2006; TOMASELLO, 2006, este artigo apresenta e discute um caso de desencontro sintático-semântico em uma Construção de Tópico do Português do Brasil. A Construção de Argumento Cindido com SN-Artefato (Meu tênis descolou o solado; O computador queimou o HD foi inicialmente descrita e analisada em pesquisa que identificou uma Família de Construção de Argumento Cindido no PB (SAMPAIO, 2010. Em uma breve apresentação de nossos pressupostos teóricos, discutimos, especialmente, o conceito de Construção e de Construção de Estrutura Argumental (GOLDBERG, 1995, 2003 e o conceito de desencontro (ou mismatch, nos termos de Francis e Michaelis (2000, Michaelis (2004 e Traugott (2007. A partir da análise de dados de uso, o estudo procura oferecer um tratamento abrangente ao fenômeno, considerando aspectos sintáticos, semânticos e pragmáticos da Construção. A análise identifica, nas instanciações dessa Construção, um desencontro no número de argumentos (um argumento semântico e dois argumentos sintáticos, e confirma a motivação pragmática desta, caracterizando-a como uma Construção de Tópico.
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Directory of Open Access Journals (Sweden)
John David Leaver
2002-05-01
Full Text Available Two preference tests were conducted with 16 lactating dairy cows in which they were allowed to choose between strawyard and cubicle housing systems. The two tests each of 14 days duration examined preferences at high and low space allowances. All cows had previous experience of both systems, but in the week prior to the preference tests, half the animals were housed in a strawyard and half in a cubicle system. This prior treatment was found to have no significant influence on subsequent choice of housing system. Continuous video recordings showed that the mean proportion of time over 14 days spent in the strawyard and cubicle areas was 66:34 at high space allowance and 68:32 at low space allowance respectively. In the second week of test at both space allowances, the total lying time proportion in the strawyard and cubicles was 91:09 indicating a strong preference to lie in the strawyard area, even when the area was restricted at the low space allowance. Social rank and dominance values were determined prior to the tests, and were found to correlate more strongly with age than with liveweight. They did not significantly influence the choice of housing system at either space allowance. The occurrence of minority preferences for the cubicle system suggests that using preference as an indicator of welfare, may lead to the development of systems which will not provide the best welfare for all animals.Dois testes de preferência foram conduzidos em 16 vacas leiteiras em lactação as quais tiveram que escolher entre confinamento com baias (com divisórias na área de repouso ou sem baias (sem divisórias na área de repouso. Os dois testes, cada um com 14 dias de duração examinaram preferência dos animais em diferentes disponibilidades de espaço. Todas as vacas tinham experiência prévia nos dois tipos de confinamentos, mas, na semana anterior aos testes de preferência, metade dos animais foram mantidos no confinamento sem baias e a outra
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Indigenous development of scanning electron microscope
International Nuclear Information System (INIS)
Ambastha, K.P.; Chaudhari, Y.V.; Pal, Suvadip; Tikaria, Amit; Pious, Lizy; Dubey, B.P.; Chadda, V.K.
2009-01-01
Scanning electron microscope (SEM) is a precision instrument and plays very important role in scientific studies. Bhabha Atomic Research Centre has taken up the job of development of SEM indigenously. Standard and commercially available components like computer, high voltage power supply, detectors etc. shall be procured from market. Focusing and scanning coils, vacuum chamber, specimen stage, control hardware and software etc. shall be developed at BARC with the help of Indian industry. Procurement, design and fabrication of various parts of SEM are in progress. (author)
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Directory of Open Access Journals (Sweden)
Diego Spader de Souza
2017-09-01
Full Text Available O objetivo do presente artigo é tecer algumas considerações iniciais a respeito de uma proposta teórico-metodológica situada na interface entre a Semântica Cognitiva e a Lexicografia. Tal proposta, atualmente sendo desenvolvida em tese de doutorado, busca a aproximação entre a teoria da Semântica de Frames, de Charles J. Fillmore, com a onomasiologia e com a produção de dicionários onomasiológicos. A onomasiologia, tema de grande importância para a Semântica Estrutural, pode ser abordada, sob nosso viés, a partir do conceito de frame semântico introduzido por Fillmore. O artigo apresenta uma discussão teórica, buscando mostrar o potencial da interface, bem como as formas através das quais a Semântica de Frames pode auxiliar a prática lexicográfica. Por se tratar de uma teoria semântica baseada em conhecimento enciclopédico, a Semântica de Frames oportuniza um modelo de dicionário onomasiológico que leva em consideração o papel da experiência e da estrutura conceptual na descrição semântica.
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Kage, S; Kudo, K; Kaizoji, A; Ryumoto, J; Ikeda, H; Ikeda, N
2001-07-01
We devised a simple and rapid method for detection of gunshot residue (GSR) particles, using scanning electron microscopy/wavelength dispersive X-ray (SEM/WDX) analysis. Experiments were done on samples containing GSR particles obtained from hands, hair, face, and clothing, using double-sided adhesive coated aluminum stubs (tape-lift method). SEM/WDX analyses for GSR were carried out in three steps: the first step was map analysis for barium (Ba) to search for GSR particles from lead styphnate primed ammunition, or tin (Sn) to search for GSR particles from mercury fulminate primed ammunition. The second step was determination of the location of GSR particles by X-ray imaging of Ba or Sn at a magnification of x 1000-2000 in the SEM, using data of map analysis, and the third step was identification of GSR particles, using WDX spectrometers. Analysis of samples from each primer of a stub took about 3 h. Practical applications were shown for utility of this method.
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In-Situ tensile testing of propellants in SEM: influence of temperature
Di Benedetto, G.L.; Ramshorst, M.C.J.; Duvalois, W.; Hooijmeijer, P.; Heijden, A. van der
2017-01-01
A tensile module system placed within a Scanning Electron Microscope (SEM) was utilized to conduct insitu tensile testing of propellant samples. The tensile module system allows for real-time in-situ SEM analysis of the samples to determine the failure mechanism of the propellant material under
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Directory of Open Access Journals (Sweden)
Francesco Mangano
2017-12-01
Full Text Available Purpose. The aim of this scanning electron microscope (SEM study was to investigate the interface between the bone and a novel nanostructured calcium-incorporated dental implant surface in humans. Methods. A dental implant (Anyridge®, Megagen Implant Co., Gyeongbuk, South Korea with a nanostructured calcium-incorporated surface (Xpeed®, Megagen Implant Co., Gyeongbuk, South Korea, which had been placed a month earlier in a fully healed site of the posterior maxilla (#14 of a 48-year-old female patient, and which had been subjected to immediate functional loading, was removed after a traumatic injury. Despite the violent trauma that caused mobilization of the fixture, its surface appeared to be covered by a firmly attached, intact tissue; therefore, it was subjected to SEM examination. The implant surface of an unused nanostructured calcium-incorporated implant was also observed under SEM, as control. Results. The surface of the unused implant showed a highly-structured texture, carved by irregular, multi-scale hollows reminiscent of a fractal structure. It appeared perfectly clean and devoid of any contamination. The human specimen showed trabecular bone firmly anchored to the implant surface, bridging the screw threads and filling the spaces among them. Conclusions. Within the limits of this human histological report, the sample analyzed showed that the nanostructured calcium-incorporated surface was covered by new bone, one month after placement in the posterior maxilla, under an immediate functional loading protocol.
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Silva, Isis dos Anjos
2014-01-01
Orientadora: Profa. Dra. Juliana Tófano de Campos Leite Toneli Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Energia, 2014. Nesse trabalho, objetivou-se avaliar a produção de biogás durante o processo de biodigestão anaeróbia de dejetos de bovinos leiteiros, com e sem a separação de sólidos, em duas etapas: na Etapa 1, foi realizada a biodigestão em 16 biodigestores do tipo batelada, com volume útil de 2L, abastecidos com dejetos obtidos em 4 diferen...
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SEM-based characterization techniques
International Nuclear Information System (INIS)
Russell, P.E.
1986-01-01
The scanning electron microscope is now a common instrument in materials characterization laboratories. The basic role of the SEM as a topographic imaging system has steadily been expanding to include a variety of SEM-based analytical techniques. These techniques cover the range of basic semiconductor materials characterization to live-time device characterization of operating LSI or VLSI devices. This paper introduces many of the more commonly used techniques, describes the modifications or additions to a conventional SEM required to utilize the techniques, and gives examples of the use of such techniques. First, the types of signals available from a sample being irradiated by an electron beam are reviewed. Then, where applicable, the type of spectroscopy or microscopy which has evolved to utilize the various signal types are described. This is followed by specific examples of the use of such techniques to solve problems related to semiconductor technology. Techniques emphasized include: x-ray fluorescence spectroscopy, electron beam induced current (EBIC), stroboscopic voltage analysis, cathodoluminescnece and electron beam IC metrology. Current and future trends of some of the these techniques, as related to the semiconductor industry are discussed
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Cai, Ting-ting; Feng, Zeng-chao; Zhou, Dong
2018-02-01
It is of great benefit to study the material and structural heterogeneity of coal for better understanding the coalbed methane (CBM) storage and enrichment. In this paper, multi-scale X-ray computed tomography (CT), scanning electron microscope (SEM) and mercury intrusion porosimetry (MIP) at multi scales were conducted to thoroughly study the material distribution, heterogeneity, pore development, porosity and permeability of coal. It is suitable and reasonable to divide the testing samples into three structural categories by average density and heterogeneity degree, and the meso structure in the three categories accords with the morphology on SEM images. The pore size distribution and pore development of each subsample cannot be correspondingly related to their respective structure category or morphology due to different observation scales, while the macro pore size development, accumulated macro pore volume and macro pores porosity accord with the meso structure category and morphology information by CT and SEM at the same scale very well. Given the effect of macro pores on permeability and the contribution of micro pores to CBM storage capacity, reservoirs with developed micro pores and macro pores may be the most suitable coal reservoir for CBM exploitation.
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Directory of Open Access Journals (Sweden)
Maria do Carmo Mohaupt Marques Ludke
2002-09-01
Full Text Available Este trabalho foi conduzido com o objetivo de comparar a eficiência de diferentes níveis de fitase em relação à suplementação de fosfato inorgânico (fosfato bicálcico, quando adicionados em dietas sem e com farelo de arroz desengordurado (FAD. Foram utilizados 128 suínos com peso inicial médio de 21,2 ± 2,4 kg, alojados em baias coletivas, para avaliar o desempenho nas fases de crescimento e terminação. Os suínos foram abatidos com peso médio de 95,4 ± 5,3 kg e coletado o osso metacarpo para determinação do cálcio e do fósforo. Foram usados oito tratamentos, sendo quatro dietas sem FAD (milho e farelo de soja e quatro dietas com 30% de inclusão de FAD, nas quais foram adicionados níveis de 0, 750 ou 1000 UF (Unidades de Fitase/kg. Foi observado que adicionar fitase, tanto em dietas sem FAD quanto em dietas com FAD, melhora a disponibilidade do fósforo orgânico. Com os níveis de 750 e 1000 UF/kg adicionados em ambas as dietas, sem suplementação de fosfato bicálcico, não houve prejuízo sobre o desempenho dos animais. Entretanto, as características ósseas são prejudicadas se as dietas com fitase não forem suplementadas com a fonte de fósforo inorgânico.The objective of this work was to compare the efficiency of different levels of phytase with the use of inorganic phosphate (dicalcium phosphate when added to diets with or without defatted rice bran (DRB. One hundred and twenty eight pigs with average initial weight of 21.6 ± 2.4 kg were housed in collective boxes for the pig performance evaluation in the growing and finishing phase. The pigs were slaughtered with an average weight of 95.42 ± 5.3 kg and the metacarpus bones were collected to determine the calcium and phosphorus content. Eight treatments were used with four diets being formulated without DRB (corn-soybean meal and the other four diets with DRB. The phytase levels added in the diets were 0, 750 or 1000 PU/kg of the diet. It was observed that
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A simplified method for scanning electron microscopy (SEM) autoradiography
International Nuclear Information System (INIS)
Shahar, A.; Lasher, R.
1980-01-01
The combination of autoradiography with SEM provides a valuable tool for the study of labeled biological materials, but the previously described methods are complicated because they call first for the removal of gelatin from the film emulsion and this is then followed by deposition of gold vapor on the specimen. The authors describe a much simpler method which can easily be adapted to routine examination of cell cultures. In this method, gelatin is not removed; the film is coated with vaporized carbon only. This procedure permits visualization of both cellular image and distribution of silver grains. (Auth.)
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DETECTION OF DELAMINATION IN A COMPOSITE PLATE BY SEM
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
A numerical method of integration of Green's functi ons of strip element method (SEM) is proposed. The response of ultrasonic sourc e generated by a transducer on the surface of a multi-ply composite plate conta ining a delamination is analyzed by the use of SEM. The numerical results show that the scanning features of the ultrasonic waves may be used to identify the d elamination inside the composite plate .
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Directory of Open Access Journals (Sweden)
Christopher Libertelli
2011-05-01
Full Text Available À medida que a indústria de telecomunicações sem fio amadurece, a consolidação e o relacionamento enFtre as empresas detentoras de infraestrutura de transporte [carriers] e os produtores de aparelhos celulares [handsets] têm revelado práticas de mercado que levantam questionamentos substanciais sobre se os consumidores estariam desfrutando de todos os benefícios possíveis oriundos da competição nas telecomunicações sem fio. Por exemplo, empresas detentoras de infraestrutura de transporte de telecomunicações têm começado a influenciar agressivamente o design de programas [software] e produtos em detrimento do consumidor. Com o amadurecimento do mercado de telecomunicações sem fio e o reconhecimento de que os aparelhos celulares tornaram-se um componente indispensável para muitos americanos, empresas detentoras de infraestrutura de transporte têm utilizado de sua considerável influência sobre o uso e design destes aparelhos para manutenção do controle e dos limites ao direito dos assinantes de executar aplicativos comunicacionais de sua escolha. Ao invés de transportarem as mensagens dos assinantes independentemente do conteúdo, empresas detentoras de infraestrutura de transporte de telecomunicações têm exercido cada vez mais controle sobre a forma como os consumidores acessam a internet móvel. Ao darem preferência a serviços próprios e ao afastarem seus rivais, ditas empresas têm desabilitado ou inutilizado interfaces amigáveis ao consumidor [consumer-friendly features] em dispositivos móveis. Além disso, as empresas detentoras de infraestrutura de transporte de telecomunicações têm implementado tais práticas em violação ao princípio Carterfone da FCC e às restrições constantes da decisão da Comissão em sua formulação original referente à autorização de venda conjugada [bundling] do terminal de acesso individual e do serviço celular. A Comissão deve agir agora para fazer valer a decis
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A combined optical, SEM and STM study of growth spirals
Indian Academy of Sciences (India)
Some novel results of a combined sequential study of growth spirals on the basal surface of the richly polytypic CdI2 crystals by optical microscopy, scanning electron microscopy (SEM) and scanning tunneling microscopy (STM) are presented and discussed. In confirmation of the known structural data, the STM pictures ...
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Directory of Open Access Journals (Sweden)
Camila Pepe
2012-07-01
Full Text Available FUNDAMENTO: O uso combinado de agentes antitrombínicos, antiplaquetários e estratégias invasivas na síndrome coronariana aguda sem supradesnivelamento do ST (SCAsSST reduz eventos cardiovasculares. O fondaparinux demonstrou equivalência à enoxaparina na redução de eventos cardiovasculares, porém com menor índice de sangramento nos pacientes que usaram fondaparinux. OBJETIVO: Avaliar o custo-efetividade de fondaparinux versus enoxaparina em pacientes com SCAsSST no Brasil a partir da perspectiva econômica do Sistema Único de Saúde (SUS. MÉTODOS: Um modelo de decisão analítico foi construído para calcular os custos e consequências resultantes dos tratamentos comparados. Os parâmetros do modelo foram obtidos do estudo OASIS-5 (N = 20.078 pacientes com SCAsSST randomizados para fondaparinux ou enoxaparina. O desfecho avaliado foi um composto de eventos cardiovasculares (isto é, morte, infarto agudo do miocárdio, isquemia refratária e sangramentos graves nos dias 9, 30 e 180 pós-SCAsSST. Foram avaliados todos os custos diretos de tratamento e eventos relacionados à SCAsSST. O ano da análise foi 2010 e os custos foram descritos em reais (R$. RESULTADOS: No dia 9, o custo de tratamento por paciente foi R$ 2.768 para fondaparinux e R$ 2.852 para enoxaparina. Aproximadamente 80% do custo total foram associados a tratamentos invasivos. Os custos com medicamentos representaram 10% do custo total. As taxas combinadas de eventos cardiovasculares e de sangramentos maiores foram 7,3% e 9,0% para fondaparinux e enoxaparina, respectivamente. Análises de sensibilidade confirmaram os resultados iniciais do modelo. CONCLUSÃO: O fondaparinux para tratamento de pacientes com SCAsSST é superior à enoxaparina em termos de prevenção de novos eventos cardiovasculares com menor custo. (Arq Bras Cardiol. 2012; [online].ahead print, PP.0-0
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Simulation of FIB-SEM images for analysis of porous microstructures.
Prill, Torben; Schladitz, Katja
2013-01-01
Focused ion beam nanotomography-scanning electron microscopy tomography yields high-quality three-dimensional images of materials microstructures at the nanometer scale combining serial sectioning using a focused ion beam with SEM. However, FIB-SEM tomography of highly porous media leads to shine-through artifacts preventing automatic segmentation of the solid component. We simulate the SEM process in order to generate synthetic FIB-SEM image data for developing and validating segmentation methods. Monte-Carlo techniques yield accurate results, but are too slow for the simulation of FIB-SEM tomography requiring hundreds of SEM images for one dataset alone. Nevertheless, a quasi-analytic description of the specimen and various acceleration techniques, including a track compression algorithm and an acceleration for the simulation of secondary electrons, cut down the computing time by orders of magnitude, allowing for the first time to simulate FIB-SEM tomography. © Wiley Periodicals, Inc.
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Mangano, Carlo; Piattelli, Adriano; Raspanti, Mario; Mangano, Francesco; Cassoni, Alessandra; Iezzi, Giovanna; Shibli, Jamil Awad
2011-01-01
Recent studies have shown that direct laser metal sintering (DLMS) produces structures with complex geometry and consequently that allow better osteoconductive properties. The aim of this patient report was to evaluate the early bone response to DLMS implant surface retrieved from human jaws. Four experimental DLMS implants were inserted in the posterior mandible of four patients during conventional dental implant surgery. After 8 weeks, the micro-implants and the surrounding tissue were removed and prepared for scanning electron microscopy (SEM) and histomorphometric analysis to evaluate the bone-implant interface. The SEM and EDX evaluations showed a newly formed tissue composed of calcium and phosphorus. The bone-to-implant contact presented a mean of 60.5 ± 11.6%. Within the limits of this patient report, data suggest that the DLMS surfaces presented a close contact with the human bone after a healing period of 8 weeks.
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Estudo comparativo entre histerectomia abdominal e vaginal sem prolapso uterino
Lisboa, Vânio Cardoso
2002-01-01
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em Ciências Médicas. Objetivo: Comparar a histerectomia abdominal e vaginal sem prolapso uterino.
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Weber, Kathryn; Delben, Juliana; Bromage, Timothy G; Duarte, Simone
2014-01-01
The study compared images of mature Streptococcus mutans biofilms captured at increasing magnification to determine which microscopy method is most acceptable for imaging the biofilm topography and the extracellular polymeric substance (EPS). In vitro S. mutans biofilms were imaged using (1) scanning electron microscopy (SEM), which requires a dehydration process; (2) SEM and ruthenium red (SEM-RR), which has been shown to support the EPS of biofilms during the SEM dehydration; and (3) variable pressure scanning electron microscopy (VPSEM), which does not require the intensive dehydration process of SEM. The dehydration process and high chamber vacuum of both SEM techniques devastated the biofilm EPS, removed supporting structures, and caused cracking on the biofilm surface. The VPSEM offered the most comprehensive representation of the S. mutans biofilm morphology. VPSEM provides similar contrast and focus as the SEM, but the procedure is far less time-consuming, and the use of hazardous chemicals associated with SEM dehydration protocol is avoided with the VPSEM. The inaccurate representations of the biofilm EPS in SEM experimentation is a possible source of inaccurate data and impediments in the study of S. mutans biofilms. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.
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The influence of environment temperature on SEM image quality
International Nuclear Information System (INIS)
Chen, Li; Liu, Junshan
2015-01-01
As the structure dimension goes down to the nano-scale, it often requires a scanning electron microscope (SEM) to provide image magnification up to 100 000 ×. However, SEM images at such a high magnification usually suffer from high resolution value and low signal-to-noise ratio, which results in low quality of the SEM image. In this paper, the quality of the SEM image is improved by optimizing the environment temperature. The experimental results indicate that at 100 000 ×, the quality of the SEM image is influenced by the environment temperature, whereas at 50 000 × it is not. At 100 000 × the best SEM image quality can be achieved from the environment temperature ranging 292 from 294 K, and the SEM image quality evaluated by the double stimulus continuous quality scale method can increase from grade 1 to grade 5. It is expected that this image quality improving method can be used in routine measurements with ordinary SEMs to get high quality images by optimizing the environment temperature. (paper)
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Sun, Cheng; Müller, Erich; Meffert, Matthias; Gerthsen, Dagmar
2018-04-01
Transmission electron microscopy (TEM) with low-energy electrons has been recognized as an important addition to the family of electron microscopies as it may avoid knock-on damage and increase the contrast of weakly scattering objects. Scanning electron microscopes (SEMs) are well suited for low-energy electron microscopy with maximum electron energies of 30 keV, but they are mainly used for topography imaging of bulk samples. Implementation of a scanning transmission electron microscopy (STEM) detector and a charge-coupled-device camera for the acquisition of on-axis transmission electron diffraction (TED) patterns, in combination with recent resolution improvements, make SEMs highly interesting for structure analysis of some electron-transparent specimens which are traditionally investigated by TEM. A new aspect is correlative SEM, STEM, and TED imaging from the same specimen region in a SEM which leads to a wealth of information. Simultaneous image acquisition gives information on surface topography, inner structure including crystal defects and qualitative material contrast. Lattice-fringe resolution is obtained in bright-field STEM imaging. The benefits of correlative SEM/STEM/TED imaging in a SEM are exemplified by structure analyses from representative sample classes such as nanoparticulates and bulk materials.
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Oxigenação extracorpórea por membrana em cães sem auxílio circulatório
Directory of Open Access Journals (Sweden)
Alessandra Castello da Costa
2014-05-01
Full Text Available A oxigenação extracorpórea por membrana com desvio arterio-venoso (AV-ECMO, em seres humanos, é uma técnica de suporte à vida capaz de assumir em parte ou totalmente as funções dos pulmões, quando estes já não são capazes de promover uma adequada hematose. Para conhecer a viabilidade deste método em cães (Canis familiaris, o presente estudo aplicou a AV-ECMO em dez indivíduos adultos, sem raça definida, com uma expectativa de três horas de duração para cada experimento. No grupo 1 (n=4, ventilação mecânica e infusão contínua de dopamina foram associadas ao suporte extracorpóreo. No grupo 2 (n=6, nenhuma medida de terapia intensiva foi instituída concomitantemente à AV-ECMO. O comportamento dos parâmetros de gasometria e os níveis de lactato foram avaliados a cada 10 minutos e 1 hora, respectivamente, por meio de da avaliação de amostras sanguíneas arteriais. O suporte inotrópico foi capaz de promover uma melhor perfusão tecidual com sangue oxigenado, sugerida pelos níveis de lactato e pressão arterial média mensurados, assim como a hemogasometria revelou melhores resultados quando a ventilação mecânica foi utilizada simultaneamente à AV-ECMO. Portanto, aplicada conjuntamente com suporte da terapia intensiva, a AV-ECMO é uma técnica viável para o uso em cães com falência respiratória, refratária aos tratamentos convencionais.
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Comparação entre troponina I cardíaca e CK-MB massa em síndrome coronariana aguda sem supra de ST
Directory of Open Access Journals (Sweden)
Elizabete Silva dos Santos
2011-03-01
Full Text Available FUNDAMENTO: Há incertezas do valor prognóstico comparativo entre troponina I cardíaca (cTnI e CK-MB em síndrome coronariana aguda (SCA. OBJETIVO: Comparar o valor prognóstico entre a cTnI e a CK-MB massa em pacientes com SCA sem supradesnível do segmento ST. MÉTODOS: Foram analisados 1.027 pacientes, de modo prospectivo, em um centro terciário de cardiologia. Combinações dos biomarcadores foram examinadas: cTnI normal, CK-MB massa normal (65,5%; cTnI normal, CK-MB massa elevada (3,9%; cTnI elevada, CK-MB massa normal (8,8%; cTnI elevada, CK-MB massa elevada (20,7%. Análise multivariada de variáveis clínicas, eletrocardiográficas e laboratoriais determinou o valor prognóstico independente dos biomarcadores para o evento de morte ou (reinfarto em 30 dias. RESULTADOS: Pacientes com pelo menos um biomarcador elevado foram mais idosos (p = 0,02 e do sexo masculino (p < 0,001. Uso prévio de aspirina (p = 0,001, betabloqueador (p = 0,003 ou estatina (p = 0,013 foi mais frequente naqueles sem elevação da cTnI. Pacientes com elevação de ambos os biomarcadores tinham mais depressão do segmento ST (p < 0,001 ou creatinina elevada (p < 0,001. Em análise multivariada com a inclusão da cTnI, a CK-MB massa não foi variável independente para o evento de morte ou (reinfarto em 30 dias (odds ratio [OR] 1,16; p = 0,71. Quando não se incluiu a cTnI, teve-se: idade (OR 1,07; p < 0,001; sexo masculino (OR 1,09; p = 0,77; diabete melito (OR 1,95; p = 0,02; acidente vascular cerebral prévio (OR 3,21; p = 0,008; creatinina elevada (OR 1,63; p = 0,002; elevação da CK-MB massa (OR 1,96; p = 0,03; estatística-C 0,77 (p < 0,001. CONCLUSÃO: Com dosagem da cTnI, a CK-MB massa pode ser dispensável para avaliação prognóstica. Na indisponibilidade da cTnI, a CK-MB massa é aceitável para decisão terapêutica.
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Infrared spectra, Raman laser, XRD, DSC/TGA and SEM ...
Indian Academy of Sciences (India)
Administrator
cussed and the X-ray diffraction, scanning electron microscopy (SEM) and atomic force microscope (AFM) ... acetamide as a simple organic compound at high tempera- ture has less ..... properties of selenium surface, AFM-microscopy tapping.
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Novel field emission SEM column with beam deceleration technology
International Nuclear Information System (INIS)
Jiruše, Jaroslav; Havelka, Miloslav; Lopour, Filip
2014-01-01
A novel field-emission SEM column has been developed that features Beam Deceleration Mode, high-probe current and ultra-fast scanning. New detection system in the column is introduced to detect true secondary electron signal. The resolution power at low energy was doubled for conventional SEM optics and moderately improved for immersion optics. Application examples at low landing energies include change of contrast, imaging of non-conductive samples and thin layers. - Highlights: • A novel field-emission SEM column has been developed. • Implemented beam deceleration improves the SEM resolution at 1 keV two times. • New column maintains high analytical potential and wide field of view. • Detectors integrated in the column allow gaining true SE and BE signal separately. • Performance of the column is demonstrated on low energy applications
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Novel field emission SEM column with beam deceleration technology
Energy Technology Data Exchange (ETDEWEB)
Jiruše, Jaroslav; Havelka, Miloslav; Lopour, Filip
2014-11-15
A novel field-emission SEM column has been developed that features Beam Deceleration Mode, high-probe current and ultra-fast scanning. New detection system in the column is introduced to detect true secondary electron signal. The resolution power at low energy was doubled for conventional SEM optics and moderately improved for immersion optics. Application examples at low landing energies include change of contrast, imaging of non-conductive samples and thin layers. - Highlights: • A novel field-emission SEM column has been developed. • Implemented beam deceleration improves the SEM resolution at 1 keV two times. • New column maintains high analytical potential and wide field of view. • Detectors integrated in the column allow gaining true SE and BE signal separately. • Performance of the column is demonstrated on low energy applications.
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Processamento de linguagem natural para indexação automática semântico-ontológica
Câmara Júnior, Auto Tavares da
2013-01-01
A pesquisa propõe uma arquitetura de indexação automática de documentos utilizando mecanismos de processamento de linguagem natural em nível semântico. Por meio do arranjo de ferramentas e recursos existentes, agregado ao desenvolvimento de software para integração, é construído um sistema de indexação automática que utiliza conhecimento modelado em uma ontologia para análise semântica. A aplicação da arquitetura é exemplificada e posta à prova em um conjunto de laudos periciais de crimes ...
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Viewing Integrated-Circuit Interconnections By SEM
Lawton, Russel A.; Gauldin, Robert E.; Ruiz, Ronald P.
1990-01-01
Back-scattering of energetic electrons reveals hidden metal layers. Experiment shows that with suitable operating adjustments, scanning electron microscopy (SEM) used to look for defects in aluminum interconnections in integrated circuits. Enables monitoring, in situ, of changes in defects caused by changes in temperature. Gives truer picture of defects, as etching can change stress field of metal-and-passivation pattern, causing changes in defects.
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Directory of Open Access Journals (Sweden)
Michel Pompeu Barros de Oliveira Sá
2010-06-01
Full Text Available INTRODUÇÃO: Tem sido bem documentado que mulheres têm taxas de morbimortalidade mais altas que homens submetidos à cirurgia de revascularização miocárdica (CRM. Em vista desta evidência, é necessário saber se há benefício da CRM sem circulação extracorpórea (CEC em comparação à CRM com CEC. OBJETIVOS: Comparar desfechos de morbimortalidade entre CRM sem CEC e CRM com CEC. MÉTODOS: Estudo retrospectivo. Nossa investigação analisa comparativamente o perfil clínico, 13 complicações relativas ao procedimento e mortalidade de uma população de 941 mulheres submetidas à CRM (549 sem CEC e 392 com CEC em dois hospitais, no período de janeiro de 2000 a dezembro de 2005. RESULTADOS: A taxa de mortalidade em mulheres submetidas à CRM sem CEC é menor que mulheres submetidas à CRM com CEC, entretanto, a diferença não é estatisticamente significativa (3,1% vs. 5,3%; P=0,134. As taxas de complicações analisadas (choque hemorrágico, neurológicas, respiratórias, insuficiência renal aguda, síndrome da angústia respiratória do adulto, septicemia, pneumonia, fibrilação atrial foram menores (diferença estatisticamente significativa em mulheres do grupo CRM sem CEC em comparação ao grupo CRM com CEC, com exceção das complicações baixo débito cardíaco e infecção de ferida operatória. CONCLUSÕES: As evidências sugerem que CRM sem CEC pode beneficiar as mulheres em comparação com CRM com CEC, pois parece reduzir as taxas de morbimortalidade. Dez das 13 complicações investigadas demonstraram uma significativa vantagem das mulheres submetidas à CRM sem CEC em relação àquelas submetidas à CRM com CEC.BACKGROUND: It has been well documented that women have higher morbidity and mortality rates than men following coronary artery bypass graft (CABG surgery. In view of this evidence, it is necessary to know if there is benefit to off-pump CABG surgery in women in comparison to on-pump CABG. OBJECTIVES: Compare
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Reference Gene Selection in the Desert Plant <em>Eremosparton songoricuem>m>
Directory of Open Access Journals (Sweden)
Dao-Yuan Zhang
2012-06-01
Full Text Available <em>Eremosparton songoricum em>(Litv. Vass. (<em>E. songoricumem> is a rare and extremely drought-tolerant desert plant that holds promise as a model organism for the identification of genes associated with water deficit stress. Here, we cloned and evaluated the expression of eight candidate reference genes using quantitative real-time reverse transcriptase polymerase chain reactions. The expression of these candidate reference genes was analyzed in a diverse set of 20 samples including various <em>E. songoricumem> plant tissues exposed to multiple environmental stresses. GeNorm analysis indicated that expression stability varied between the reference genes in the different experimental conditions, but the two most stable reference genes were sufficient for normalization in most conditions.<em> EsEFem> and <em>Esα-TUB> were sufficient for various stress conditions, <em>EsEF> and <em>EsACT> were suitable for samples of differing germination stages, and <em>EsGAPDH>and <em>Es
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Hrubanova, Kamila; Nebesarova, Jana; Ruzicka, Filip; Krzyzanek, Vladislav
2018-04-22
In this study we present an innovative method for the preparation of fully hydrated samples of microbial biofilms of cultures Staphylococcus epidermidis, Candida parapsilosis and Candida albicans. Cryo-scanning electron microscopy (cryo-SEM) and high-pressure freezing (HPF) rank among cutting edge techniques in the electron microscopy of hydrated samples such as biofilms. However, the combination of these techniques is not always easily applicable. Therefore, we present a method of combining high-pressure freezing using EM PACT2 (Leica Microsystems), which fixes hydrated samples on small sapphire discs, with a high resolution SEM equipped with the widely used cryo-preparation system ALTO 2500 (Gatan). Using a holder developed in house, a freeze-fracturing technique was applied to image and investigate microbial cultures cultivated on the sapphire discs. In our experiments, we focused on the ultrastructure of the extracellular matrix produced during cultivation and the relationships among microbial cells in the biofilm. The main goal of our investigations was the detailed visualization of areas of the biofilm where the microbial cells adhere to the substrate/surface. We show the feasibility of this technique, which is clearly demonstrated in experiments with various freeze-etching times. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Assessment of Paint Layers by FE-SEM and EDS Examination
National Research Council Canada - National Science Library
Harris, Donovan
2004-01-01
.... The approach was to remove free-film samples from each panel, fracture the films, and then examine at high magnification the cross sections using a field emission-scanning electron microscope (FE-SEM...
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Bianca RÜCKERT; Marília Carla de Mello GAIA
2014-01-01
Este artigo analisa o desenvolvimento de uma ação educativa em segurança alimentar e nutricional envolvendo o Movimento dos Trabalhadores Rurais Sem Terra, na região Metropolitana de Belo Horizonte, Minas Gerais. A partir do registro da experiência, enfatizou-se a metodologia da ação, os saberes mobilizados e as mudanças nas práticas de saúde, segurança alimentar e produção agropecuária dos sujeitos envolvidos. As reflexões apontam para alguns elementos da metodologia que contribuíram para o ...
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SEM: A user's manual for materials science
International Nuclear Information System (INIS)
Gabriel, B.L.
1985-01-01
This book provides a reference of techniques used by the metallurgical microscopist. It contains an introduction to the instrumentation and methods of scanning electron microscopy with historical as well as state-of-the-art methodologies. Topics covered include: SEM instrumentation, photography, energy dispersive spectroscopy, introduction to sample preparation, polished samples, fracture surfaces, replicas and thin films
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Energy Technology Data Exchange (ETDEWEB)
Montanari Migliavacca, Daniela [Instituto de Biociencias, Programa de Pos-Graduacao em Ecologia, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91509-900 Porto Alegre, RS (Brazil); Fundacao Estadual de Protecao Ambiental Henrique Luis Roessler, RS. Rua Carlos Chagas 55/802, 90030-020 Porto Alegre, RS (Brazil); Calesso Teixeira, Elba, E-mail: gerpro.pesquisa@fepam.rs.gov.br [Fundacao Estadual de Protecao Ambiental Henrique Luis Roessler, RS. Rua Carlos Chagas 55/802, 90030-020 Porto Alegre, RS (Brazil); Gervasoni, Fernanda; Vieira Conceicao, Rommulo [Instituto de Geociencias, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91509-900 Porto Alegre, RS (Brazil); Raya Rodriguez, Maria Teresa [Instituto de Biociencias, Programa de Pos-Graduacao em Ecologia, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91509-900 Porto Alegre, RS (Brazil)
2009-11-15
The purpose of this study is to assess the composition of wet precipitation in three sites of the metropolitan area of Porto Alegre. Besides the variables usually considered, such as pH, conductivity, major ions (Cl{sup -}, NO{sub 3}{sup -}, F{sup -}, SO{sub 4}{sup 2-}, Na{sup +}, K{sup +}, Mg{sup 2+}, NH{sub 4}{sup +} and Ca{sup 2+}) and metallic elements (Cd, Co, Cr, Cu, Fe, Mn and Ni), the suspended matter was examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM), with energy dispersive system (EDS), for better identification of possible anthropogenic material in this wet precipitation. Results showed an alkaline pH in the samples analyzed and higher concentrations for Na{sup +}, Cl{sup -} and SO{sub 4}{sup 2-}. The acidification and neutralization potential between anions (SO{sub 4}{sup 2-} + NO{sub 3}{sup -}) and cations (Ca{sup 2+} + Mg{sup 2+} + K{sup +} + NH{sub 4}{sup +}) showed a good correlation (0.922). The metallic elements with highest values were Zn, Fe and Mn. Results of XRD identified the presence of some minerals such as quartz, feldspar, mica, clay, carbonates and sulfates. In samples analyzed with SEM, we detected pyroxene, biotite, amphibole and oxides. Cluster analysis (CA) was applied to the data matrix to identify potential pollution sources of metals (natural or anthropogenic) and the association with minerals found in the analysis of SEM.
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Incidência de tremor em anestesia peridural com ou sem fentanil: estudo comparativo
Directory of Open Access Journals (Sweden)
Abreu Múcio Paranhos de
2004-01-01
Full Text Available JUSTIFICATIVA E OBJETIVOS: A maioria dos trabalhos encontrados na literatura, relacionando a influência dos opióides administrados por via peridural com o tremor intra e pós-operatório, foram realizados com grupos de pacientes obstétricas, nas quais a resposta do centro termorregulador pode ser diferente das pacientes não grávidas. O objetivo deste trabalho foi comparar o bloqueio peridural com e sem fentanil, quanto à incidência de tremores e outras complicações no intra e pós-operatório em pacientes submetidos à cirurgia de varizes sob anestesia peridural com bupivacaína a 0,5% com adrenalina a 1:200.000. MÉTODO: Trinta e quatro pacientes, estado físico ASA I e II, submetidos à cirurgia para tratamento de varizes de membros inferiores, foram divididos aleatoriamente em 2 grupos (n = 17, e receberam midazolam (0,05 mg.kg-1, por via venosa seguido de anestesia peridural lombar, utilizando-se no grupo S, 20 ml bupivacaína a 0,5% (com vasoconstritor associado a 2 ml de solução fisiológica a 0,9% e no grupo F, 20 ml de bupivacaína a 0,5% (com vasoconstritor associada ao fentanil (100 µg. Foram estudados: incidência de tremor, temperatura dos pacientes, necessidade do uso de meperidina, e a incidência de náuseas e vômitos nos seguintes momentos: M1 - admissão do paciente na sala de operação; M2 - imediatamente antes da anestesia; M3 - 30 minutos após o término da injeção do anestésico local; M4 - 60 minutos após o término da injeção do anestésico local; M5 - 90 minutos após o término da injeção do anestésico local; M6 - final da anestesia; M7 - antecedendo a alta da sala de recuperação pós-anestésica. RESULTADOS: Quanto aos dados antropométricos, estado físico, tempo médio de duração da anestesia e cirurgia, temperatura dos pacientes e da sala de operação e incidência de náuseas e vômitos não houve diferença estatística entre os grupos. Houve diferença estatística aos 60 minutos (M4 e
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Recent advances in 3D SEM surface reconstruction.
Tafti, Ahmad P; Kirkpatrick, Andrew B; Alavi, Zahrasadat; Owen, Heather A; Yu, Zeyun
2015-11-01
The scanning electron microscope (SEM), as one of the most commonly used instruments in biology and material sciences, employs electrons instead of light to determine the surface properties of specimens. However, the SEM micrographs still remain 2D images. To effectively measure and visualize the surface attributes, we need to restore the 3D shape model from the SEM images. 3D surface reconstruction is a longstanding topic in microscopy vision as it offers quantitative and visual information for a variety of applications consisting medicine, pharmacology, chemistry, and mechanics. In this paper, we attempt to explain the expanding body of the work in this area, including a discussion of recent techniques and algorithms. With the present work, we also enhance the reliability, accuracy, and speed of 3D SEM surface reconstruction by designing and developing an optimized multi-view framework. We then consider several real-world experiments as well as synthetic data to examine the qualitative and quantitative attributes of our proposed framework. Furthermore, we present a taxonomy of 3D SEM surface reconstruction approaches and address several challenging issues as part of our future work. Copyright © 2015 Elsevier Ltd. All rights reserved.
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A methodological basis for SEM autoradiography: biosynthesis and radioligand binding
International Nuclear Information System (INIS)
Cheng, G.; Hodges, G.M.; Trejdosiewicz, L.K.
1985-01-01
A method is described for scanning electron microscope (SEM) autoradiography whereby preservation of high resolution cell surface details is retained together with degelatination of the emulsion without gross loss or redistribution of silver grains. This method should provide a convenient medium-sized marker for SEM (using secondary, backscattered electron and X-ray imaging) topographic studies of biosynthesized molecules, and of cell surface receptors and antigens, using indirect or direct labelling procedures with radio-labelled ligands. (author)
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Directory of Open Access Journals (Sweden)
Juvenal da Rocha Torres Neto
2007-12-01
Full Text Available O preparo intestinal é muito utilizado em cirurgias do cólon. A LIATO (lavagem intestinal anterógrada trans-operatória promove limpeza do cólon, conferindo incremento de tempo ao ato cirúrgico e maior risco de infecção pela maior manipulação do conteúdo intestinal .Este estudo compara confecção de anastomoses colônicas com e sem preparo intestinal, pela análise histomorfométrica. Foram submetidos à cirurgia 30 coelhos divididos em 2 grupos: grupo 1, controle e grupo 2, que submeteu-se a LIATO, e comparados os seus resultados. A presença de infiltrado inflamatório agudo teve média discretamente maior nas anastomoses do grupo 2. Infiltrado inflamatório crônico obteve média de 1,9 nas anastomoses do grupo 2 e de 2,1 nas sem preparo. Necrose esteve presente em 15,7% dos casos onde se realizou LIATO contra 13,5% no grupo sem preparo. Calcificações foram encontradas em 43% das anastomoses com preparo e em 30% das sem preparo. Observou-se maior quantidade de colágeno nas anastomoses feitas com a lavagem intestinal. O padrão entrelaçado das fibras colágenas foi observado em 86% das anastomoses do grupo 2 e 70% no 1. Estudo estatístico foi realizado com programa Prism® 4 para pColon laudering is used in many colon surgeries. The LIATO, that promotes cleanness of colon, demonstrates an increase of the surgical time and increase risk of infection. This study compares colonic anastomosis with and without preparation, through histomorfometric analysis. 30 rabbits were submitted to the surgery treatment and had been evaluated and divided in groups: group 1 (control and group 2 (LIATO. Carried through statistical study with the program Prism® 4 for p< 5%. The analisis found acute inflammatory infiltrated with discrete bigger average in the anastomoses of group 2. Chronic inflammatory infiltrated with average of 1,9 in the anastomoses of group 2 and of 2,1 in the ones without preparation. Necrosis in 15,7% in the LIATO against 13
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Ellingham, Sarah T D; Thompson, Tim J U; Islam, Meez
2018-03-01
This study investigates the use of Scanning electron microscopy-energy-dispersive X-ray (SEM-EDX) as a diagnostic tool for the determination of the osseous origin of samples subjected to different temperatures. Sheep (Ovis aries) ribs of two experimental groups (fleshed and defleshed) were burned at temperatures of between 100°C and 1100°C in 100°C increments and subsequently analyzed with the SEM-EDX to determine the atomic percentage of present elements. Three-factor ANOVA analysis showed that neither the exposure temperature, nor whether the burning occurred with or without soft tissue present had any significant influence on the bone's overall elemental makeup (p > 0.05). The Ca/P ratio remained in the osseous typical range of between 1.6 and 2.58 in all analyzed samples. This demonstrates that even faced with high temperatures, the overall gross elemental content and atomic percentage of elements in bone remain stable, creating a unique "fingerprint" for osseous material, even after exposure to extreme conditions. © 2017 American Academy of Forensic Sciences.
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Directory of Open Access Journals (Sweden)
Rosana Marques Silva
2004-02-01
Full Text Available Utilizaram-se 24 gatas gestantes, sem raça definida, doadas para o estudo da vascularização arterial dos cornos uterinos. Em 20 animais, com o intervalo gestacional entre 7 e 9 semanas, a aorta abdominal foi injetada com Látex-Neoprene 650 corado, associado ao Sulfato de Bário 1004. Os animais foram então radiografados, fixados em solução aquosa de formol 10% e dissecados para estudo da distribuição dos vasos arteriais destinados às regiões paraplacentárias e de cintas placentárias. Em 4 animais realizou-se o exame por Ecografia Power Doppler, onde se observou que nas regiões das cintas placentárias o índice de resistência dos vasos apresenta-se menor do que o encontrado ao longo da artéria uterina. Em todas as observações, a artéria uterina é o principal vaso a irrigar os cornos uterinos, emitindo de 2 a 17 ramos, com maior freqüência de 5 a 12 ramos, os quais se distribuem nas regiões paraplacentárias e/ou das cintas placentárias, formando arcadas anastomósticas. Não houve diferenças estatísticas significativas do número de ramos para cada região individualmente, porém a análise das radiografias contrastadas demonstrou haver uma concentração maior de contraste nas regiões das cintas placentárias. A artéria ovárica participa da vascularização arterial da extremidade cranial dos cornos uterinos, onde se anastomosa com ramos da artéria uterina.
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SEM visualization of glycosylated surface molecules using lectin-coated microspheres
Duke, J.; Janer, L.; Campbell, M.
1985-01-01
There are several techniques currently used to localize glycosylated surface molecules by scanning electron microscopy (Grinnell, 1980; Molday, 1976; Linthicum and Sell, 1975; Nicolson, 1974; Lo Buglio, et al, 1972). A simple and rapid method, using a modification of Grinnell's technique is reported here. Essentially, microspheres coated with Concavalin A are used to bind to glycosylated regions of the palatal shelf epithelium and are visualized in the scanning electron microscope (SEM).
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e-Science Semântica: integração dos dados na comunicação científica
Directory of Open Access Journals (Sweden)
Elizabete Cristina de Souza de Aguiar Monteiro
2016-06-01
Full Text Available Nos paradigmas da ciência, as ciências experimentais, teóricas e computacionais estão sendo afetadas pelo grande quantidade de dados coletados ou simulados e emergi um novo paradigma, o paradigma do uso intensivo de dados, denominado por pesquisadores de e-Science, ou quarto paradigma da ciência. Dessa forma, tornar esse quarto paradigma em semântico, em que os dados e a literatura científica estejam integrados, lincados, disponíveis e interoperáveis, é um desafio. Novas ferramentas e linguagens são necessárias e projetos para tornar isso possível estão sendo apresentados. Sendo assim, o artigo teve como objetivo a caracterização de 3 sitios, Molecular BioSystems, Solar-Terrestre Virtual e revista Nature que têm melhorias semânticas e uso de ontologias em suas páginas, verificando a correlação entre a Web semântica e e-Science. A metodologia utilizada consistiu no levantamento bibliográfico e revisão de literatura para discussão do tema, uso do método descritivo para descrever as características semânticas dos portais, além do método comparativo. Verificamos que a aplicação da web semântica em portais com características da e-science melhora consideravelmente a recuperação e, consequentemente a reutilização de dados primários de pesquisa.
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Spin-polarized scanning electron microscopy
International Nuclear Information System (INIS)
Kohashi, Teruo
2014-01-01
Spin-Polarized Scanning Electron Microscopy (Spin SEM) is one way for observing magnetic domain structures taking advantage of the spin polarization of the secondary electrons emitted from a ferromagnetic sample. This principle brings us several excellent capabilities such as high-spatial resolution better than 10 nm, and analysis of magnetization direction in three dimensions. In this paper, the principle and the structure of the spin SEM is briefly introduced, and some examples of the spin SEM measurements are shown. (author)
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SEM Investigation of Superheater Deposits from Biomass-Fired Boilers
DEFF Research Database (Denmark)
Jensen, Peter Arendt; Frandsen, Flemming; Hansen, Jørn
2004-01-01
, mature superheater deposit samples were extracted from two straw-fired boilers, Masnedø and Ensted, with fuel inputs of 33 MWth and 100 MWth, respectively. SEM (scanning electron microscopy) images and EDX (energy dispersive X-ray) analyses were performed on the deposit samples. Different strategies...
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ASAPP: Alinhamento Semântico Automático de Palavras aplicado ao Português
Directory of Open Access Journals (Sweden)
Ana Oliveira Alves
2016-12-01
Full Text Available Apresentamos duas abordagens distintas à tarefa de avaliação conjunta ASSIN onde, dada uma coleção de pares de frases escritas em português, são colocados dois objectivos para cada par: (a calcular a similaridade semântica entre as duas frases; e (b verificar se uma frase do par é paráfrase ou inferência da outra. Uma primeira abordagem, apelidada de Reciclagem, baseia-se exclusivamente em heurísticas sobre redes semânticas para a língua portuguesa. A segunda abordagem, apelidada de ASAPP, baseia-se em aprendizagem automática supervisionada. Acima de tudo, os resultados da abordagem Reciclagem permitem comparar, de forma indireta, um conjunto de redes semânticas, através do seu desempenho nesta tarefa. Estes resultados, algo modestos, foram depois utilizados como características da abordagem ASAPP, juntamente com características adicionais, ao nível lexical e sintático. Após comparação com os resultados da coleção dourada, verifica-se que a abordagem ASAPP supera a abordagem Reciclagem de forma consistente. Isto ocorre tanto para o Português Europeu como para o Português Brasileiro, onde o desempenho atinge uma exatidão de 80.28% +- 0.019 para a inferência textual, enquanto que a correlação dos valores atribuídos para a similaridade semântica com aqueles atribuídos por humanos é de 66.5% +- 0.021.
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Application of SEM and EDX in studying biomineralization in plant tissues.
He, Honghua; Kirilak, Yaowanuj
2014-01-01
This chapter describes protocols using formalin-acetic acid-alcohol (FAA) to fix plant tissues for studying biomineralization by means of scanning electron microscopy (SEM) and qualitative energy-dispersive X-ray microanalysis (EDX). Specimen preparation protocols for SEM and EDX mainly include fixation, dehydration, critical point drying (CPD), mounting, and coating. Gold-coated specimens are used for SEM imaging, while gold- and carbon-coated specimens are prepared for qualitative X-ray microanalyses separately to obtain complementary information on the elemental compositions of biominerals. During the specimen preparation procedure for SEM, some biominerals may be dislodged or scattered, making it difficult to determine their accurate locations, and light microscopy is used to complement SEM studies. Specimen preparation protocols for light microscopy generally include fixation, dehydration, infiltration and embedding with resin, microtome sectioning, and staining. In addition, microwave processing methods are adopted here to speed up the specimen preparation process for both SEM and light microscopy.
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Surface topography characterization using 3D stereoscopic reconstruction of SEM images
Vedantha Krishna, Amogh; Flys, Olena; Reddy, Vijeth V.; Rosén, B. G.
2018-06-01
A major drawback of the optical microscope is its limitation to resolve finer details. Many microscopes have been developed to overcome the limitations set by the diffraction of visible light. The scanning electron microscope (SEM) is one such alternative: it uses electrons for imaging, which have much smaller wavelength than photons. As a result high magnification with superior image resolution can be achieved. However, SEM generates 2D images which provide limited data for surface measurements and analysis. Often many research areas require the knowledge of 3D structures as they contribute to a comprehensive understanding of microstructure by allowing effective measurements and qualitative visualization of the samples under study. For this reason, stereo photogrammetry technique is employed to convert SEM images into 3D measurable data. This paper aims to utilize a stereoscopic reconstruction technique as a reliable method for characterization of surface topography. Reconstructed results from SEM images are compared with coherence scanning interferometer (CSI) results obtained by measuring a roughness reference standard sample. This paper presents a method to select the most robust/consistent surface texture parameters that are insensitive to the uncertainties involved in the reconstruction technique itself. Results from the two-stereoscopic reconstruction algorithms are also documented in this paper.
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Caetano, Priscilla Kárim; FCA/UNESP; Mendonça, Veridiana Zoocoler de; FCA/UNESP; Daiuto, Érica Regina; Faculdade de Ciências Agronômicas (FCA/UNESP-Botucatu); Vieites, Rogério Lopes; FCA/UNESP
2015-01-01
Objetivou-se nesta pesquisa verificar a preferência sensorial entre compota e doce em calda de figo calda em função do modo de preparo. Foram realizados três tratamentos: compota de figo - tratamento térmico por 20 minutos, sem cozimento do fruto na calda (T1), doce de figo em calda - tratamento térmico dos frutos por 10 minutos e cozimento dos frutos na calda por 10 minutos (T2) e doce de figo em calda - sem tratamento térmico e cozimento do fruto na calda por 20 minutos (T3). A calda utili...
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Barbosa, Rogério Zanarde [UNESP
2015-01-01
Este é um trabalho de tecnologia computacional aplicada na área agrícola, cujo objetivo principal do trabalho é desenvolver uma rede de sensores sem fio, que envolve aspectos de software e hardware, para o monitoramento térmico no interior de uma casa de vegetação. Além da rede propriamente dita, o trabalho também inclui a sua aplicação no levantamento quantitativo da variabilidade térmica na casa de vegetação o que pode ser aplicado em diversas atividades agrícolas a serem desenvolvidas no i...
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The principle of electron microscopy; SEM and TEM
International Nuclear Information System (INIS)
Fauzi, S.H.
1992-01-01
The article reviews the principle of electron microscopy which is used in scanning electron microscope (SEM) and transmission electron microscope (TEM). These instruments are important for the examination and analysis of the microstructural properties of solid objects. Relevance physical concept lies behind the devices are given. The main components of each device are also discussed
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Refração por retinoscopia com luz em faixa em cães
Ranzani,J.J.T.; Mobricci,L.A.L.; Carvalho,L.R.; Brandão,C.V.S.
2008-01-01
A refração ocular por retinoscopia com luz em faixa em 10 cães normais, sem raça definida, demonstrou que a maioria dos animais, independentemente do porte, apresentou tendência à hipermetropia, além de anisometropia e astigmatismo.
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Directory of Open Access Journals (Sweden)
P.H.C. Silva
2009-10-01
Full Text Available Estudou-se a topografia post mortem do cone medular em 30 gatos adultos sem raça definida. Procedeu-se à remoção da pele e da musculatura dorsal da coluna vertebral e expuseram-se a medula espinhal e seus envoltórios, após a secção dos arcos vertebrais. O cone medular foi evidenciado e mensurado. Avaliou-se a sua relação com as vértebras lombares (L, sacrais (S e caudais (Cd. O cone medular variou de 3,40 a 8,00cm (média=5,08cm. A esqueletopia foi variável, pois em 24 (80% animais o cone medular iniciou-se na vértebra L6; em quatro (13,3%, na L7; e em dois (6,7%, na L5. Em 12 (40% animais terminou na vértebra S2; em 10 (33,3%, na S3; em cinco (16,7%, na Cd1; em dois (6,7%, na S1; e em um (3,3% na Cd2.It was studied the post mortem topography of the medullar cone in 30 adult non-defined breed cats. The dorsal skin and muscles from the vertebral column were removed and the spinal cord and its wrappers were visualized, after the section of the vertebral arcs. The medullar cone was then exposed and measured. Its relationship with lumbar (L, sacral (S, and caudal (Cd vertebrae was determined. The length of the medullar cone presented a variation from 3.40 to 8.00cm (average 5.08cm. Its skeletopy was variable; since in 24 animals (80%, the medullar cone began at the L6 vertebra; in four (13.3%, at the L7; and in two (6.7% at the L5 vertebra. It ended in 12 (40% animals at the S2 vertebra; in 10 (33,33%, at the S3; in five (16.7% at the caudal (Cd vertebra; in two (6.7%, at the S1; and in one (3.3%, at the Cd2.
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Nanomanufacturing concerns about measurements made in the SEM Part III: vibration and drift
Postek, Michael T.; Vladár, András. E.; Cizmar, Petr
2014-08-01
Many advanced manufacturing processes employ scanning electron microscopes (SEM) for on-line critical measurements for process and quality control. This is the third of a series of papers discussing various causes of measurement uncertainty in scanned particle beam instruments, and some of the solutions researched and developed at NIST. Scanned particle beam instruments especially the scanning electron microscope have gone through tremendous evolution to become indispensable tools for many and diverse scientifi c and industrial applications. These improvements have signifi cantly enhanced their performance and made them far easier to operate. But, ease of operation has also fostered operator complacency. In addition, the user-friendliness has reduced the need for extensive operator training. Unfortunately, this has led to the concept that the SEM is just another expensive digital camera or another peripheral device connected to a computer and that all of the issues related to obtaining quality data have been solved. Hence, a person (or company) using these instruments may be lulled into thinking that all of the potential pitfalls have been fully eliminated and they believe everything they see on the micrograph is always correct. But, as described in this and the earlier presentations this may not be the case. The fi rst paper in this series discussed some of the issues related to signal generation in the SEM, including instrument calibration, electron beam-sample interactions and the need for physics-based modelling to understand the actual image formation mechanisms to properly interpret SEM images. The second paper, discussed another major issue confronting the microscopist: specimen contamination and methods of contamination elimination. This third paper, discusses vibration and drift and some useful solutions.
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Two novel approaches to study arthropod anatomy by using dualbeam FIB/SEM.
Di Giulio, Andrea; Muzzi, Maurizio
2018-03-01
Transmission Electron Microscopy (TEM) has always been the conventional method to study arthropod ultrastructure, while the use of Scanning Electron Microscopy (SEM) was mainly devoted to the examination of the external cuticular structures by secondary electrons. The new generation field emission SEMs are capable to generate images at sub-cellular level, comparable to TEM images employing backscattered electrons. The potential of this kind of acquisition becomes very powerful in the dual beam FIB/SEM where the SEM column is combined with a Focused Ion Beam (FIB) column. FIB uses ions as a nano-scalpel to slice samples fixed and embedded in resin, replacing traditional ultramicrotomy. We here present two novel methods, which optimize the use of FIB/SEM for studying arthropod anatomy. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Directory of Open Access Journals (Sweden)
Luiz Carlos Rosemberg
2000-01-01
Full Text Available Estudamos a distribuição e o arranjo vascular arterial dos ramos à glândula mamária em 30 caprinos sem raça definida, adultos, oriundos dos estados do Ceará e Minas Gerais, mediante a análise de esquemas de modelos obtidos pela injeção de látex "neoprene" 450, fixação em formol a 10% e dissecção. O suprimento sangüíneo de cada metade do úbere faz-se pela A. pudenda externa, complementado por conexões com ramos das Aa. pudenda interna e torácica interna. Próximo ao úbere a A. pudenda externa curva-se cranialmente, emite o ramo mamário superficial, torna-se A. mamária até a sua bifurcação; emite ainda ramos aos linfonodos mamários e à região labial ventral da vulva. Ao penetrar na glândula a A. mamária bifurca-se dando origem às Aa. mamárias cranial e medial que enviam diversos ramos à glândula em geral e pele da região. A A. mamária cranial percorre cranialmente a parede abdominal ventral como A. epigástrica caudal superficial. Não existem diferenças significativas entre os arranjos vasculares dos dois antímeros da mama. Ocorrem anastomoses entre as Aa. mamárias mediais e seus ramos. Fizemos uma análise comparativa do nosso trabalho em relação a outros estudos a respeito da irrigação da glândula mamária em ruminantes.
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Directory of Open Access Journals (Sweden)
Fernanda Barcellos Serralta
2010-04-01
Full Text Available Na literatura internacional, a experiência de quase-morte (EQM é avaliada principalmente por meio do instrumento The Near-Death Experience Scale (NDE, elaborado por Bruce Greyson, em 1983. O objetivo do presente estudo é verificar a existência de equivalência semântica entre a versão original da escala (em inglês e a versão traduzida ao português do Brasil, avaliando os significados geral e referencial. Após as diversas etapas de avaliação da equivalência semântica, a escala foi pré-testada em seis pacientes internados após alta de um Centro de Tratamento Intensivo (CTI de um Hospital Universitário. Na avaliação realizada por dois psicólogos e dois psiquiatras, constatou-se existir equivalência semântica entre a versão final em português e o original. Na aplicação da escala na população-alvo, verificou-se boa compreensão dos itens. Portanto, a escala está adequada à cultura brasileira, podendo ser utilizada para pesquisas sobre Experiências de Quase-Morte neste contexto.In the international literature, near-death experiences are often measured by The Near-Death Experience Scale (NDE, developed by Bruce Greyson in 1983. The aim of this study is to verify the existence of the semantic equivalence between the original version (in English and the translated version to Brazilian Portuguese, evaluating both the general and the referential meaning. The semantic evaluation was conducted according to the several steps. Thereafter, a pre-testing was performed in six post Intensive Care Unit patients of a University Hospital. The evaluations of two psychologists and two psychiatrists have found existence of semantic equivalence between the Brazilian and the original version of the scale. The pre-test applied on the target population proved the items were intelligible. Our findings suggest that the Brazilian version of the NDE might be used in the investigation of near-death experience in Brazilian culture.
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International Nuclear Information System (INIS)
Siti Zulaiha Hairaldin; Wan Md Zin Wan Yunus; Norazowa Ibrahim
2011-01-01
In this study, Octadecylamine Modified Montmorillonites (ODAMMT) were used to prepare Poly lactide/ Polycaprolactone (PLA/ PCL) nano composites. PLA and PCL mix in 90:10 ratios, using an internal mixer by melt blending technique. The other sample was blend with Natrium Montmorillonite (NaMMT) and Octadecylamine Modified Montmorillonite (ODA-MMT) to produce PLA/ PCL-NaMMT and PLA/ PCL ODAMMT. To characterize the polymer nano composites, X-ray diffraction (XRD), FTIR and SEM analysis were conducted. Comparison of morphology were made up between PLA/ PCL, PLA/ PCL with presence of 7 % of Na-MMT and 7 % ODA-MMT respectively based on SEM micrograph by calculate the number-average diameter. (author)
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Directory of Open Access Journals (Sweden)
Yévenes López, Ismael
2010-01-01
Full Text Available Objetivo: Determinar a prevalência e severidade da doença cárie dentária em crianças pré-escolares de 3 a 5 anos de idade em creches no Chile, localizadas em uma comunidade sem fluoretação da água de abastecimento público e em outra comunidade com agua fluoretada. Metodologia: Delineamento do estudo: observacional, transversal. A amostra foi composta por 200 crianças de 3 a 5 anos, com boa saúde geral, pertencentes a baixos estratos sociais, de quatro creches da Região Metropolitana de Santiago, dois do município de Maipú sem fluoretação da água de abastecimento público e duas do município de Peñalolén com fluoretação desde 1996, com concentração de flúor de 0,6 mg/L. A metodologia da OMS foi utilizada para o registro da percentagem de crianças livres de cárie e o índice cpod foi usado para medir a severidade da doença. Resultados: A porcentagem de crianças livres de cárie foi de 24% em Maipú e 55% em Peñalolén, com índice cpod de 3,38 e 1,84, respectivamente. Estes resultados aumentaram com a idade. Conclusão: A prevalência e severidade da cárie dentária em pré-escolares de 3 a 5 anos em Maipú (agua não fluoretada foram superiores aos observados em Peñalolén (água fluoretada
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Directory of Open Access Journals (Sweden)
Rodrigo de Castro BERNARDES
1998-10-01
Full Text Available O tratamento cirúrgico dos aneurismas toracoabominais exige toracofreno laparotomia, períodos prolongados de pinçamento aórtico com isquemia visceral, sangramento abundante de difícil controle, complicações pulmonares, renais, neurológicas e distúrbios de coagulação com morbimortalidade muitas vezes proibitiva para pacientes de idade avançada, ou portadores de distúrbios respiratórios, renais ou cardíacos prévios. A rotura aumenta em muito a já elevada taxa de morbimortalidade. Crawford (1-3 e Borst (4 descreveram operação em dois tempos para tratamento de aneurisma que atinge mais de um segmento da aorta, com bons resultados. O objetivo de nosso trabalho é mostrar a técnica cirúrgica em dois tempos, empregando prótese intraluminal sem sutura (5, 6. Esta técnica nos proporciona uma operação menos agressiva por abordar somente o segmento roto da aorta, portanto apenas uma cavidade é manipulada (tórax ou abdome. A anastomose com prótese intraluminal reduz em muito o tempo de pinçamento da aorta e, conseqüentemente, a isquemia visceral, diminuindo, também, o sangramento. A redução da agressividade cirúrgica sobre estes pacientes já gravemente enfermos nos proporcionou bons resultados cirúrgicos.The surgical management of thoracoabdominal aneurysms requires thoracophrenic laparotomy, prolonged periods of aortic clamping with visceral ischemia, profuse bleeding leading to a difficult postoperative course with pulmonary, renal, neurological complications, coagulation disturbances and others. All this resulting in an elevated morbidity/mortality very often contraindicating it for the very elderly or those with prior respiratory, renal or cardiac symptoms. Rupture of this aneurysm greatly increases the already high rate of morbidity/mortality. Crawford and Borst have described a two-stage surgery with good results, for aneurysms that affect more than one segment of aorta. The objective of our report is to demonstrate
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Wi-Fi Salvador: mapeamento colaborativo e redes sem fio no Brasil
Lemos, André; Pastor, Leonardo; Oliveira, Nelson
2012-01-01
O trabalho faz uma breve demonstração de políticas públicas para inclusão digital por meio da disponibilização do acesso à internet por meio de redes sem fio e discute a forma como as pessoas se relacionam com os lugares, de acordo com a existência ou inexistência de acessibilidade à internet. O objetivo é discutir o acesso à internet pelas redes sem fio no Brasil e, mais especificamente, na cidade de Salvador. Este trabalho é fruto de pesquisa realizada no âmbito do Grupo de Pesquisa em Cibe...
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SEM facility for examination of reactive and radioactive materials
International Nuclear Information System (INIS)
Downs, G.L.; Tucker, P.A.
1977-01-01
A scanning electron microscope (SEM) facility for the examination of tritium-containing materials is operational at Mound Laboratory. The SEM is installed with the sample chamber incorporated as an integral part of an inert gas glovebox facility to enable easy handling of radioactive and pyrophoric materials. A standard SEM (ETEC Model B-1) was modified to meet dimensional, operational, and safety-related requirements. a glovebox was designed and fabricated which permitted access with the gloves to all parts of the SEM sample chamber to facilitate director and accessory replacement and repairs. A separate console combining the electron optical column and specimen chamber was interfaced to the glovebox by a custom-made, neoprene bellows so that the vibrations normally associated with the blowers and pumps were damped. Photomicrographs of tritiated pyrophoric materials show the usefulness of this facility. Some of the difficulties involved in the investigation of these materials are also discussed. The SEM is also equipped with an energy dispersive x-ray detector (ORTEC) and a Secondary Ion Mass Spectrometer (3M) attachments. This latter attachment allows analysis of secondary ions with masses ranging from 1-300 amu. (Auth.)
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GAGG:ce single crystalline films: New perspective scintillators for electron detection in SEM.
Bok, Jan; Lalinský, Ondřej; Hanuš, Martin; Onderišinová, Zuzana; Kelar, Jakub; Kučera, Miroslav
2016-04-01
Single crystal scintillators are frequently used for electron detection in scanning electron microscopy (SEM). We report gadolinium aluminum gallium garnet (GAGG:Ce) single crystalline films as a new perspective scintillators for the SEM. For the first time, the epitaxial garnet films were used in a practical application: the GAGG:Ce scintillator was incorporated into a SEM scintillation electron detector and it showed improved image quality. In order to prove the GAGG:Ce quality accurately, the scintillation properties were examined using electron beam excitation and compared with frequently used scintillators in the SEM. The results demonstrate excellent emission efficiency of the GAGG:Ce single crystalline films together with their very fast scintillation decay useful for demanding SEM applications. Copyright © 2016 Elsevier B.V. All rights reserved.
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Cultivo sem solo do morangueiro Strawberry soilless cultivation
Directory of Open Access Journals (Sweden)
Gustavo Giménez
2008-02-01
Full Text Available O morangueiro é uma cultura importante em vários países, principalmente nos Estados Unidos e na Europa, por suas características sensoriais, propriedades nutritivas e por sua rentabilidade. O cultivo comercial sem solo de morangueiro está bem desenvolvido na Europa, onde tem permitido um aumento da produtividade e qualidade da produção assim como a ampliação da oferta do produto ao longo do ano. Predomina o sistema aberto, em sacolas ou vasos com diferentes tipos de substratos, utilizando-se densidades de 8 a 12plantas m-2. As produtividades obtidas estão entre 5 e 10kg m-2. Para isolar as plantas do solo e facilitar o manejo da cultura, os vasos ou sacolas são suspensos a uma altura entre 0,8 e 1m da superfície do solo. A composição da solução nutritiva é variável, refletindo as diferentes condições produtivas. As mudas são produzidas principalmente em bandejas com substrato, a partir de pontas de estolões obtidas da multiplicação de plantas matrizes provenientes da propagação in vitro. No Brasil, o cultivo sem solo de morangueiro é ainda incipiente e os resultados produtivos e econômicos têm sido insatisfatórios, principalmente por falta de informações de pesquisas capazes de indicar sistemas apropriados de cultivo para as condições locais. É necessário desenvolver sistemas sustentáveis, preferencialmente fechados, combinando alta produtividade e elevada eficiência de utilização da água e dos nutrientes. No presente trabalho, são revisados os principais aspectos da produção em sistemas de cultivo sem solo de mudas e fruta de morangueiro. São descritos a produção de mudas, os sistemas e as soluções nutritivas empregadas em diferentes países. Ao final, são feitas inferências sobre a possibilidade de adoção e geração do sistema de cultivo sem solo apropriado para as condições brasileiras.Strawberry is a very important crop in Europe and USA due to its nutritional and sensorial
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International Nuclear Information System (INIS)
Sababi, Majid; Ejnermark, Sebastian; Andersson, Jörgen; Claesson, Per M.; Pan, Jinshan
2013-01-01
Highlights: ► Localized corrosion of a new N-based tool alloy (Fe–Cr–V–N) has been studied. ► One-pass mode of scanning Kelvin force microscopy (KFM) was used in the study. ► The focus was on correlation between microstructure and localized corrosion. - Abstract: Microstructure influence on corrosion behavior of an N-based tool alloy (Fe–Cr–V–N) has been studied. Electron microscopy analysis showed two types of hard phases in the alloy. One-pass mode scanning Kelvin force microscopy (KFM) was used to investigate relative nobility of the hard phases. Volta potential mapping indicates higher nobility for the hard phases than the alloy matrix, and, the V- and N-rich particles exhibit the highest Volta potential. Post-polarization analysis by SEM revealed localized dissolution initiated in matrix regions adjacent to hard phase particles, and the boundary region surrounding the Cr- and Mo-rich particles is more prone to localized corrosion.
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A Student-Built Scanning Tunneling Microscope
Ekkens, Tom
2015-01-01
Many introductory and nanotechnology textbooks discuss the operation of various microscopes including atomic force (AFM), scanning tunneling (STM), and scanning electron microscopes (SEM). In a nanotechnology laboratory class, students frequently utilize microscopes to obtain data without a thought about the detailed operation of the tool itself.…
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Raman-in-SEM, a multimodal and multiscale analytical tool: performance for materials and expertise.
Wille, Guillaume; Bourrat, Xavier; Maubec, Nicolas; Lahfid, Abdeltif
2014-12-01
The availability of Raman spectroscopy in a powerful analytical scanning electron microscope (SEM) allows morphological, elemental, chemical, physical and electronic analysis without moving the sample between instruments. This paper documents the metrological performance of the SEMSCA commercial Raman interface operated in a low vacuum SEM. It provides multiscale and multimodal analyses as Raman/EDS, Raman/cathodoluminescence or Raman/STEM (STEM: scanning transmission electron microscopy) as well as Raman spectroscopy on nanomaterials. Since Raman spectroscopy in a SEM can be influenced by several SEM-related phenomena, this paper firstly presents a comparison of this new tool with a conventional micro-Raman spectrometer. Then, some possible artefacts are documented, which are due to the impact of electron beam-induced contamination or cathodoluminescence contribution to the Raman spectra, especially with geological samples. These effects are easily overcome by changing or adapting the Raman spectrometer and the SEM settings and methodology. The deletion of the adverse effect of cathodoluminescence is solved by using a SEM beam shutter during Raman acquisition. In contrast, this interface provides the ability to record the cathodoluminescence (CL) spectrum of a phase. In a second part, this study highlights the interest and efficiency of the coupling in characterizing micrometric phases at the same point. This multimodal approach is illustrated with various issues encountered in geosciences. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Bok, Jan; Schauer, Petr
2014-01-01
In the paper, the SEM detector is evaluated by the modulation transfer function (MTF) which expresses the detector's influence on the SEM image contrast. This is a novel approach, since the MTF was used previously to describe only the area imaging detectors, or whole imaging systems. The measurement technique and calculation of the MTF for the SEM detector are presented. In addition, the measurement and calculation of the detective quantum efficiency (DQE) as a function of the spatial frequency for the SEM detector are described. In this technique, the time modulated e-beam is used in order to create well-defined input signal for the detector. The MTF and DQE measurements are demonstrated on the Everhart-Thornley scintillation detector. This detector was alternated using the YAG:Ce, YAP:Ce, and CRY18 single-crystal scintillators. The presented MTF and DQE characteristics show good imaging properties of the detectors with the YAP:Ce or CRY18 scintillator, especially for a specific type of the e-beam scan. The results demonstrate the great benefit of the description of SEM detectors using the MTF and DQE. In addition, point-by-point and continual-sweep e-beam scans in SEM were discussed and their influence on the image quality was revealed using the MTF. © 2013 Wiley Periodicals, Inc.
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Marcelo Adriano Duart
2008-01-01
O uso de adições minerais em concretos é um tema bastante estudado por vários pesquisadores que buscam características como: redução do consumo de cimento para redução de custos, aumento da durabilidade, aumento da resistência mecânica e aproveitamento de resíduos industriais para redução da poluição ambiental. Este estudo pretende analisar a microestrutura dos concretos dosados com adição de cinza de casca de arroz residual sem controle de queima e sem moagem (CCAN), em substitui...
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GAGG:ce single crystalline films: New perspective scintillators for electron detection in SEM
International Nuclear Information System (INIS)
Bok, Jan; Lalinský, Ondřej; Hanuš, Martin; Onderišinová, Zuzana; Kelar, Jakub; Kučera, Miroslav
2016-01-01
Single crystal scintillators are frequently used for electron detection in scanning electron microscopy (SEM). We report gadolinium aluminum gallium garnet (GAGG:Ce) single crystalline films as a new perspective scintillators for the SEM. For the first time, the epitaxial garnet films were used in a practical application: the GAGG:Ce scintillator was incorporated into a SEM scintillation electron detector and it showed improved image quality. In order to prove the GAGG:Ce quality accurately, the scintillation properties were examined using electron beam excitation and compared with frequently used scintillators in the SEM. The results demonstrate excellent emission efficiency of the GAGG:Ce single crystalline films together with their very fast scintillation decay useful for demanding SEM applications. - Highlights: • First practical application of epitaxial garnet films demonstrated in SEM. • Improved image quality of SEM equipped with GAGG:Ce single crystalline thin film scintillator. • Scintillation properties of GAGG:Ce films compared with standard bulk crystal scintillators.
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Directory of Open Access Journals (Sweden)
Caio Vitor Beojone
Full Text Available Resumo O estudo de Sistemas de Atendimento Emergencial – SAE visa encontrar meios de fornecer serviços de saúde efetivos e melhorar a qualidade de vida da população respeitando as limitações de recursos disponíveis. Nesse contexto, o objetivo do presente trabalho foi mostrar o potencial de aplicação do modelo hipercubo com prioridade na fila com mais de um servidor preferencial sem considerar a hipótese de backup parcial em Sistemas de Atendimento Móvel de Urgência – SAMU em que o nível de utilização do sistema é relativamente baixo. Para isso foram realizados alguns experimentos do modelo hipercubo com prioridade na fila sem backup parcial e prospecção de cenários futuros por meio de um estudo de caso no SAMU da cidade de Bauru, SP. Foram avaliados os impactos do aumento na demanda sobre o sistema e o quanto e como (aonde localizar? a aquisição de uma nova ambulância pode melhorar as medidas de desempenho do sistema. Os principais resultados mostram que um aumento de 50% na demanda pode dobrar o tempo de resposta dessas ambulâncias, por outro lado, aumentos mais discretos têm um impacto pequeno sobre o sistema, como pode ser visto nos aumentos de 5,71% e 13,57%, nos quais o acréscimo nos tempos de resposta foram de 5% e 16%, respectivamente. A aquisição de uma nova ambulância foi avaliada em termos das medidas de desempenho e os melhores resultados em todos os cenários se deu quando ela estava presente no átomo Boulevard, obtendo um tempo médio de resposta 3% inferior às demais localidades, em média.
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A Proposal on the Quantitative Homogeneity Analysis Method of SEM Images for Material Inspections
Energy Technology Data Exchange (ETDEWEB)
Kim, Song Hyun; Kim, Jong Woo; Shin, Chang Ho [Hanyang University, Seoul (Korea, Republic of); Choi, Jung-Hoon; Cho, In-Hak; Park, Hwan Seo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2015-05-15
A scanning electron microscope (SEM) is a method to inspect the surface microstructure of materials. The SEM uses electron beams for imaging high magnifications of material surfaces; therefore, various chemical analyses can be performed from the SEM images. Therefore, it is widely used for the material inspection, chemical characteristic analysis, and biological analysis. For the nuclear criticality analysis field, it is an important parameter to check the homogeneity of the compound material for using it in the nuclear system. In our previous study, the SEM was tried to use for the homogeneity analysis of the materials. In this study, a quantitative homogeneity analysis method of SEM images is proposed for the material inspections. The method is based on the stochastic analysis method with the information of the grayscales of the SEM images.
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A Proposal on the Quantitative Homogeneity Analysis Method of SEM Images for Material Inspections
International Nuclear Information System (INIS)
Kim, Song Hyun; Kim, Jong Woo; Shin, Chang Ho; Choi, Jung-Hoon; Cho, In-Hak; Park, Hwan Seo
2015-01-01
A scanning electron microscope (SEM) is a method to inspect the surface microstructure of materials. The SEM uses electron beams for imaging high magnifications of material surfaces; therefore, various chemical analyses can be performed from the SEM images. Therefore, it is widely used for the material inspection, chemical characteristic analysis, and biological analysis. For the nuclear criticality analysis field, it is an important parameter to check the homogeneity of the compound material for using it in the nuclear system. In our previous study, the SEM was tried to use for the homogeneity analysis of the materials. In this study, a quantitative homogeneity analysis method of SEM images is proposed for the material inspections. The method is based on the stochastic analysis method with the information of the grayscales of the SEM images
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Directory of Open Access Journals (Sweden)
Roberto Leiser BARONAS
2009-07-01
Full Text Available Neste ,trabalho do mirante da Análise de Discurso francesa analisamos textualizações do discurso político em Programas de Governo de candidatos a presidente do Brasil das últimas eleições. Trabalhamos como o tema Corrupção foi dado a circular nesses distintos programas de governo. Mobilizamos inicialmente o conceito de formação discursiva, elaborado por Courtine (2007 em Análise do discurso: o discurso comunista endereçado aos cristãos, procurando verificar como os enunciados que dizem o tema Corrupção se inscrevem numa rede de filiações tanto interdiscursivas quanto intradiscursivas e, por último, li luz do conceito de semântica global elaborado por Maingueneau (2005, em Gênese dos discursos. verificamos como esse tema é regrado por um conjunto de restrições semânticas que autoriza. aquilo que pode e deve ser dito pelo discurso. Tais restrições afetam a intertextualidade; o vocabulário; os temas; o estatuto do enunciador e do destinatário: a dêixis enunciativa; o modo de enunciação, a vocalidade e o modo de coesão do discurso. O corpus de análise constitui-se por recortes dos Programas de Governo dos candidatos: Cristovam Buarque PDT, Geraldo Alkmin PSDB, Luiz Inácio da Silva PT e Heloísa Helena PSOL. A escolha dos Planos dos candidatos se justifica pela classificação que obtiveram no processo eleitoral de 2006.
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Directory of Open Access Journals (Sweden)
Roberto Leiser BARONAS
2013-11-01
Full Text Available Neste ,trabalho do mirante da Análise de Discurso francesa analisamos textualizações do discurso político em Programas de Governo de candidatos a presidente do Brasil das últimas eleições. Trabalhamos como o tema Corrupção foi dado a circular nesses distintos programas de governo. Mobilizamos inicialmente o conceito de formação discursiva, elaborado por Courtine (2007 em Análise do discurso: o discurso comunista endereçado aos cristãos, procurando verificar como os enunciados que dizem o tema Corrupção se inscrevem numa rede de filiações tanto interdiscursivas quanto intradiscursivas e, por último, li luz do conceito de semântica global elaborado por Maingueneau (2005, em Gênese dos discursos. verificamos como esse tema é regrado por um conjunto de restrições semânticas que autoriza. aquilo que pode e deve ser dito pelo discurso. Tais restrições afetam a intertextualidade; o vocabulário; os temas; o estatuto do enunciador e do destinatário: a dêixis enunciativa; o modo de enunciação, a vocalidade e o modo de coesão do discurso. O corpus de análise constitui-se por recortes dos Programas de Governo dos candidatos: Cristovam Buarque PDT, Geraldo Alkmin PSDB, Luiz Inácio da Silva PT e Heloísa Helena PSOL. A escolha dos Planos dos candidatos se justifica pela classificação que obtiveram no processo eleitoral de 2006.
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A combined SEM, CV and EIS study of multi-layered porous ceramic reactors for flue gas purification
DEFF Research Database (Denmark)
He, Zeming; Andersen, Kjeld Bøhm; Nygaard, Frederik Berg
2013-01-01
The effect of sintering temperature of 12-layered porous ceramic reactors (comprising 5 cells) was studied using scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The difference in microstructures of the reactors was evaluated by SEM...
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Information or resolution: Which is required from an SEM to study bulk inorganic materials?
Xing, Q
2016-11-01
Significant technological advances in scanning electron microscopy (SEM) have been achieved over the past years. Different SEMs can have significant differences in functionality and performance. This work presents the perspectives on selecting an SEM for research on bulk inorganic materials. Understanding materials demands quantitative composition and orientation information, and informative and interpretable images that reveal subtle differences in chemistry, orientation/structure, topography, and electronic structure. The capability to yield informative and interpretable images with high signal-to-noise ratios and spatial resolutions is an overall result of the SEM system as a whole, from the electron optical column to the detection system. The electron optical column determines probe performance. The roles of the detection system are to capture, filter or discriminate, and convert signal electrons to imaging information. The capability to control practical operating parameters including electron probe size and current, acceleration voltage or landing voltage, working distance, detector selection, and signal filtration is inherently determined by the SEM itself. As a platform for various accessories, e.g. an energy-dispersive spectrometer and an electron backscatter diffraction detector, the properties of the electron optical column, specimen chamber, and stage greatly affect the performance of accessories. Ease-of-use and ease-of-maintenance are of practical importance. It is practically important to select appropriate test specimens, design suitable imaging conditions, and analyze the specimen chamber geometry and dimensions to assess the overall functionality and performance of an SEM. For an SEM that is controlled/operated with a computer, the stable software and user-friendly interface significantly improve the usability of the SEM. SCANNING 38:864-879, 2016. © 2016 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.
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Directory of Open Access Journals (Sweden)
Carlos Alfredo Lopes de Carvalho
2011-03-01
Full Text Available Polygyny, characterized by the presence of several egg-laying queens, is considered as a temporary colony status. In stingless bees it is rarely observed. This paper reports the first case of natural polygyny in Melipona scutellaris colony, with five egg-laying queens.Poliginia, caracterizada pela presença de mais de uma rainha poedeira, é considerada como uma condição temporária em colônias. Em abelhas sem ferrão isso é raramente observado. Este artigo registra o primeiro caso de poliginia natural em colônia de Melipona scutellaris, com cinco rainhas poedeiras.
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Elida Ferreira Martins
2015-01-01
Neste trabalho, enfocamos um aspecto do léxico do português que diz respeito aos neologismos semânticos, bem como sua abordagem no ensino de Língua Portuguesa no Brasil. O objetivo principal da pesquisa consiste em analisar, qualitativamente, os neologismos semânticos encontrados em textos publicitários de revistas noticiosas de circulação nacional, a partir de uma perspectiva pedagógica. Para a constituição do corpus de neologismos, utilizamos uma amostra do Acervo Digital da revista Veja...
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Theoretical analysis of moiré fringe multiplication under a scanning electron microscope
International Nuclear Information System (INIS)
Li, Yanjie; Xie, Huimin; Chen, Pengwan; Zhang, Qingming
2011-01-01
In this study, theoretical analysis and experimental verification of fringe multiplication under a scanning electron microscope (SEM) are presented. Fringe multiplication can be realized by enhancing the magnification or the number of scanning lines under the SEM. A universal expression of the pitch of moiré fringes is deduced. To apply this method to deformation measurement, the calculation formulas of strain and displacement are derived. Compared to natural moiré, the displacement sensitivity is increased by fringe multiplication while the strain sensitivity may be retained or enhanced depending on the number of scanning lines used. The moiré patterns are formed by the interference of a 2000 lines mm −1 grating with the scanning lines of SEM, and the measured parameters of moiré fringes from experimental results agree well with theoretical analysis
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Directory of Open Access Journals (Sweden)
Marildo de Oliveira Lopes
2017-02-01
Full Text Available Este artigo objetiva discutir, por meio de uma análise linguística, a construção de sentidos possibilitada pelos encadeamentos argumentativos evocados nas falas dos deputados Ronaldo Fonseca e Jean Wyllys, em um debate acerca do Estatuto da Família - Projeto de Lei 6.583/13 - que objetiva restringir o conceito de família aos casais heterossexuais e filho (s. Essa análise se dá à luz da Teoria dos Blocos Semânticos (TBS, criada por Oswald Ducrot e Marion Carel (2005, fase mais expressiva da Teoria da Argumentação na Língua (ANL. A TBS defende que a argumentação está na própria língua e que discursos são evocados por meio de encadeamentos argumentativos – que são a combinação de dois segmentos de um enunciado, unidos pelos conectores PORTANTO (DC e NO ENTANTO (PT, que estabelecem interdependência semântica entre eles. Um encadeamento argumentativo pertence a um bloco semântico composto de quatro aspectos argumentativos. Para atingir nosso propósito, transcrevemos o debate em questão, realizamos um estudo bibliográfico acerca do tema e prosseguimos com a análise do nosso corpus. Selecionamos dois excertos das falas de cada debatedor que melhor ilustram a evocação de encadeamentos argumentativos. Isso nos possibilitou elaborar quatro aspectos argumentativos para o bloco semântico defendido por cada deputado e mais quatro aspectos argumentativos que compõem o bloco oposto. Nossos dados comprovam que a própria língua possui orientação argumentativa e que os sentidos são construídos a partir da argumentação. Além disso, confirmamos que a argumentação é materializada na relação entre entidades linguísticas.
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Permanent magnet finger-size scanning electron microscope columns
Energy Technology Data Exchange (ETDEWEB)
Nelliyan, K., E-mail: elenk@nus.edu.sg [Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 (Singapore); Khursheed, A. [Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 (Singapore)
2011-07-21
This paper presents permanent magnet scanning electron microscope (SEM) designs for both tungsten and field emission guns. Each column makes use of permanent magnet technology and operates at a fixed primary beam voltage. A prototype column operating at a beam voltage of 15 kV was made and tested inside the specimen chamber of a conventional SEM. A small electrostatic stigmator unit and dedicated scanning coils were integrated into the column. The scan coils were wound directly around the objective lens iron core in order to reduce its size. Preliminary experimental images of a test grid specimen were obtained through the prototype finger-size column, demonstrating that it is in principle feasible.
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Permanent magnet finger-size scanning electron microscope columns
International Nuclear Information System (INIS)
Nelliyan, K.; Khursheed, A.
2011-01-01
This paper presents permanent magnet scanning electron microscope (SEM) designs for both tungsten and field emission guns. Each column makes use of permanent magnet technology and operates at a fixed primary beam voltage. A prototype column operating at a beam voltage of 15 kV was made and tested inside the specimen chamber of a conventional SEM. A small electrostatic stigmator unit and dedicated scanning coils were integrated into the column. The scan coils were wound directly around the objective lens iron core in order to reduce its size. Preliminary experimental images of a test grid specimen were obtained through the prototype finger-size column, demonstrating that it is in principle feasible.
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Directory of Open Access Journals (Sweden)
Ítalo A. Sherlock
1976-02-01
Full Text Available Foi verificada a transmissão sucessiva do T. cruzi em três gerações da cobaia Cavia porcellus sem a participação de triatomíneos. Embora não fosse determinado qual das vias, se placentária, leite, excreções ou contágio direto pelo qual o protozoário foi transmitido para os descendentes, chama-se atenção para a importância da manutenção de reservatórios da Doença de Chagas, mesmo na ausência de vetores invertebrados.
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Reputação e Web Semântica: estudo comparativo de buscas aplicado a blogs
Directory of Open Access Journals (Sweden)
Sandra Portella Montardo
2010-01-01
Full Text Available Os blogs merecem a atenção das organizações, pois são uma forma fácil e gratuita de as pessoas publicarem sua opinião, inclusive sobre marcas. Este artigo compara as buscas possíveis de blogs em motores de busca convencionais e com a Web Semântica (ontologia. A marca selecionada foi o iPhone, supertelefone lançado pela Apple em 2007. Percebe-se que a busca proporcionada pela Web Semântica é mais refinada, pois permite a construção de relações entre os termos pesquisados, o que se torna pertinente para o gerenciamento da reputação de imagem corporativa.
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Orientation mapping by transmission-SEM with an on-axis detector
International Nuclear Information System (INIS)
Fundenberger, J.J.; Bouzy, E.; Goran, D.; Guyon, J.; Yuan, H.; Morawiec, A.
2016-01-01
Conventional orientation mapping in a scanning electron microscope (SEM) is a valuable technique for characterizing crystalline materials, but its application to ultrafine or nano-grain materials is limited by its spatial resolution. The resolution can be increased by collecting transmission diffraction patterns in SEM. In previous works, such patterns were collected using off-axis detectors in nearly vertical position. To avoid some drawbacks of such arrangement, a new configuration was devised in which the scintillator is located underneath the thin foil on the optical axis of the microscope, and the light is reflected towards the camera by a mirror. This simple configuration gives intense patterns even at very low probe currents, and can be potentially used for collecting maps of relatively high spatial resolution. Example maps reveal details with dimensions of about 5 nm. Because of its resolution and geometric simplicity, the proposed configuration will open new opportunities in SEM-based characterization of nanocrystalline materials. - Highlights: • New experimental configuration for SEM-based orientation mapping is presented. • The geometry of recording transmission Kikuchi patterns in SEM is simplified. • The new configuration allows for reaching relatively high spatial resolution.
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Comparison of multilayered nanowire imaging by SEM and Helium Ion Microscopy
International Nuclear Information System (INIS)
Inkson, B J; Peng, Y; Jepson, M A E; Rodenburg, C; Liu, X
2010-01-01
The helium ion microscope (HeIM) is capable of probe sizes smaller than SEM and, with intrinsically small ion/sample interaction volumes, may therefore potentially offer higher spatial resolution secondary electron (SE) imaging of nanostructures. Here 55 nm diameter CoPt/Pt multilayered nanowires have been imaged by HeIM, SEM and TEM. It is found that there is an increased resolution of nanowire surface topography in HeIM SE images compared to SEM, however there is a reduction of materials contrast of the alternating Pt and CoPt layers. This can be attributed to the increased contribution of surface contamination layers to the ion-induced SE signal, and carbon is also observed to grow on the nanowires under prolonged HeIM scanning.
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The Effect of Nonnormality on CB-SEM and PLS-SEM Path Estimates
Z. Jannoo; B. W. Yap; N. Auchoybur; M. A. Lazim
2014-01-01
The two common approaches to Structural Equation Modeling (SEM) are the Covariance-Based SEM (CB-SEM) and Partial Least Squares SEM (PLS-SEM). There is much debate on the performance of CB-SEM and PLS-SEM for small sample size and when distributions are nonnormal. This study evaluates the performance of CB-SEM and PLS-SEM under normality and nonnormality conditions via a simulation. Monte Carlo Simulation in R programming language was employed to generate data based on the theoretical model w...
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High resolution SEM characterization of nano-precipitates in ODS steels.
Jóźwik, Iwona; Strojny-Nędza, Agata; Chmielewski, Marcin; Pietrzak, Katarzyna; Kurpaska, Łukasz; Nosewicz, Szymon
2018-05-01
The performance of the present-day scanning electron microscopy (SEM) extends far beyond delivering electronic images of the surface topography. Oxide dispersion strengthened (ODS) steel is on of the most promising materials for the future nuclear fusion reactor because of its good radiation resistance, and higher operation temperature up to 750°C. The microstructure of ODS should not exceed tens of nm, therefore there is a strong need in a fast and reliable technique for their characterization. In this work, the results of low-kV SEM characterization of nanoprecipitates formed in the ODS matrix are presented. Application of highly sensitive photo-diode BSE detector in SEM imaging allowed for the registration of single nm-sized precipitates in the vicinity of the ODS alloys. The composition of the precipitates has been confirmed by TEM-EDS. © 2018 Wiley Periodicals, Inc.
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Afasia global sem hemiparesia: relato de caso
SILVA,MARCUS TULIUS TEIXEIRA DA; CAVALCANTI,JOSÉ LUÍS DE SÁ; MOREIRA,DENISE MADEIRA
2000-01-01
Afasia global geralmente é acompanhada por hemiparesia direita devido à extensão da lesão subjacente. Recentemente têm sido registrados na literatura casos em que tal síndrome ou não se acompanha do déficit motor ou este é apenas transitório, sendo esta condição conhecida como afasia global sem hemiparesia (AGSH). Relatamos caso de AGSH devido a infarto cerebral embólico cardiogênico, corroborando a tese de que esta condição pode ter valor preditivo para o diagnóstico de infartos embólicos....
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Surface characteristics of isopod digestive gland epithelium studied by SEM.
Millaku, Agron; Leser, Vladka; Drobne, Damjana; Godec, Matjaz; Torkar, Matjaz; Jenko, Monika; Milani, Marziale; Tatti, Francesco
2010-05-01
The structure of the digestive gland epithelium of a terrestrial isopod Porcellio scaber has been investigated by conventional scanning electron microscopy (SEM), focused ion beam-scanning electron microscopy (FIB/SEM), and light microscopy in order to provide evidence on morphology of the gland epithelial surface in animals from a stock culture. We investigated the shape of cells, extrusion of lipid droplets, shape and distribution of microvilli, and the presence of bacteria on the cell surface. A total of 22 animals were investigated and we found some variability in the appearance of the gland epithelial surface. Seventeen of the animals had dome-shaped digestive gland "normal" epithelial cells, which were densely and homogeneously covered by microvilli and varying proportions of which extruded lipid droplets. On the surface of microvilli we routinely observed sparsely distributed bacteria of different shapes. Five of the 22 animals had "abnormal" epithelial cells with a significantly altered shape. In three of these animals, the cells were much smaller, partly or completely flat or sometimes pyramid-like. A thick layer of bacteria was detected on the microvillous border, and in places, the shape and size of microvilli were altered. In two animals, hypertrophic cells containing large vacuoles were observed indicating a characteristic intracellular infection. The potential of SEM in morphological investigations of epithelial surfaces is discussed.
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Human cardiac telocytes: 3D imaging by FIB-SEM tomography.
Cretoiu, D; Hummel, E; Zimmermann, H; Gherghiceanu, M; Popescu, L M
2014-11-01
Telocyte (TC) is a newly identified type of cell in the cardiac interstitium (www.telocytes.com). TCs are described by classical transmission electron microscopy as cells with very thin and long telopodes (Tps; cellular prolongations) having podoms (dilations) and podomers (very thin segments). TCs' three-dimensional (3D) morphology is still unknown. Cardiac TCs seem to be particularly involved in long and short distance intercellular signalling and, therefore, their 3D architecture is important for understanding their spatial connections. Using focused ion beam scanning electron microscopy (FIB-SEM) we show, for the first time, the whole ultrastructural anatomy of cardiac TCs. 3D reconstruction of cardiac TCs by FIB-SEM tomography confirms that they have long, narrow but flattened (ribbon-like) telopodes, with humps generated by the podoms. FIB-SEM tomography also confirms the network made by TCs in the cardiac interstitium through adherens junctions. This study provides the first FIB-SEM tomography of a human cell type. © 2014 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.
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Sobrecarga de trabalho da Enfermagem e incidentes e eventos adversos em pacientes internados em UTI
Directory of Open Access Journals (Sweden)
Marcia Cristina Zago Novaretti
2014-10-01
Full Text Available Estudo prospectivo, tipo coorte que visou identificar a influência da sobrecarga de trabalho da Enfermagem na ocorrência de incidentes sem lesão e eventos adversos em 399 pacientes internados em Unidades de Terapia Intensiva (UTI. Para coleta de dados, foi aplicado um questionário estruturado e feita análise de prontuários. Nessas admissões, aproximadamente 78% dos incidentes sem lesão e eventos adversos em pacientes foram relacionados à esfera da Enfermagem. Essas ocorrências foram atribuídas à sobrecarga de trabalho, aumentaram o número de dias de internação e o risco de óbito dos pacientes estudados. É fundamental que os gerentes de enfermagem atuem no processo de gestão de pessoas no âmbito hospitalar, evitando a sobrecarga de trabalho e proporcionando, consequentemente, aumento da segurança do paciente.
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Dynamic Low-Vacuum Scanning Electron Microscope Freeze Drying Observation for Fresh Water Algae
International Nuclear Information System (INIS)
Mohsen, H.T.; Ghaly, W.A.; Zahran, N.F.; Helal, A.I.
2010-01-01
A new perpetration method for serving in dynamic examinations of the fresh water algae is developed in connection with the Low-Vacuum Scanning Electron Microscope (LV-SEM) freeze drying technique. Specimens are collected from fresh water of Ismailia channel then transferred directly to freeze by liquid nitrogen and dried in the chamber of the scanning electron microscope in the low vacuum mode. Scanning electron micrographs revealed that the drying method presented the microstructure of algae. Dehydration in a graded ethanol series is not necessary in the new method. Dried algae specimen is observed in SEM high vacuum mode after conductive coating at higher resolution. Low-vacuum SEM freeze drying technique is a simple, time-saving and reproducible method for scanning electron microscopy that is applicable to various aquatic microorganisms covered with soft tissues.
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Directory of Open Access Journals (Sweden)
Denis Martinez
2016-01-01
Full Text Available Introdução: A apneia obstrutiva do sono (AOS afeta a anatomia e função do coração. Ocorre hipertensão arterial em metade dos casos de AOS, dificultando atribuir a etiologia dessas alterações separadamente à hipertensão arterial ou à apneia do sono. Métodos: Estudo transversal de pacientes com índice de apneia-hipopneia maior que 50 eventos por hora. As variáveis ecocardiográficas comparadas em indivíduos com hipertensão arterial controlada e não controlada foram: 1 fração de ejeção, 2 diâmetro da aorta, 3 diâmetro do átrio esquerdo, 4 diâmetro de ventrículo direito, 5 diâmetros do ventrículo esquerdo diastólico e sistólico, 6 percentagem delta, 7 espessura do septo, 8 espessura da parede posterior. Resultados: Foram incluídos 83 voluntários, 50 com pressão arterial não controlada. Em média, a idade era 47±9,5 anos, o índice de massa corporal 34±5,4 Kg/m2, o índice de apneia-hipopneia 86±18 eventos/hora. Sessenta pacientes apresentaram anormalidade no ecocardiograma. A hipertrofia de ventrículo esquerdo foi o achado mais comum, sem diferença de frequência em controles (39% e em hipertensos (48%, seguida por disfunção diastólica em controles (27% e em hipertensos (32%. Conclusões: Indivíduos com apneia do sono grave e pressão arterial controlada apresentam alterações no ecocardiograma de tipo e frequência semelhantes aos com hipertensão não controlada. Isso sugere que a apneia do sono pode causar dano cardíaco independentemente de hipertensão. Quando não explicáveis por hipertensão arterial, achados como hipertrofia de ventrículo esquerdo podem ser provocados por apneia do sono. Introduction: Obstructive sleep apnea (OSA affects the cardiac anatomy and function. Hypertension occurs in half the OSA cases, making it difficult to attribute the cause of these changes separately to arterial hypertension or sleep apnea. Methods: Prospective cross-sectional study of volunteers with apnea
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Spina bifida in a dead stillbirth mongrel dog/ Spinha bífida em um cão natimorto sem raça definida
Directory of Open Access Journals (Sweden)
Selwyn Arlington Headley
2007-10-01
Full Text Available Spina bifida is a congenital spinal deformity that is characterized by an incomplete closure of the dorsal portion of the vertebrate. This report describes the radiological and pathological findings of this abnormality in a dead still birth mongrel. The dog demonstrated a cleft at the dorsal region of the thoracic vertebrate column, which resulted in exposition and protrusion of the spinal cord and the meninges. Plain radiographs of the ventral-dorsal of the vertebrate column revealed a defect in the fusion of the dorsal spinous processes of the distal thoracic vertebrates (T6 – T13; while the right-lateral view revealed xyphosis of the entire lumbar region of the spine.A espinha bífida é uma deformidade congênita caracterizada pelo incompleto fechamento da porção dorsal de uma ou mais vértebras. O presente caso descreve as alterações radiológicas e patológicas de um cão natimorto sem raça definida. O animal apresentava uma fissura nas vértebras torácicas, resultando em exposição e protusão da medula espinhal e meninges. O exame radiográfico simples em posição ventro dorsal das vértebras revelou defeito na fusão do processo espinhoso das vértebras torácicas (T6-T13, enquanto na radiografia lateral foi observada cifose em toda região lombar.
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Surface properties and microporosity of polyhydroxybutyrate under scanning electron microscopy
International Nuclear Information System (INIS)
Raouf, A.A.; Samsudin, A.R.; Samian, R.; Akool, K.; Abdullah, N.
2004-01-01
This study was designed to investigate the surface properties especially surface porosity of polyhydroxybutyrate (PHB) using scanning electron microscopy. PHB granules were sprinkled on the double-sided sticky tape attached on a SEM aluminium stub and sputtered with gold (10nm thickness) in a Polaron SC515 Coater, following which the samples were placed into the SEM specimen chamber for viewing and recording. Scanning electron micrographs with different magnification of PHB surface revealed multiple pores with different sizes. (Author)
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Bonifazi, G.; Capobianco, G.; Serranti, S.; Eggimann, M.; Wagner, E.; Di Maio, F.; Lotfi, S.
2015-01-01
Aim of this work was to investigate the microstructure of the Interfacial Transition Zone (ITZ) between cement paste and aggregate in concrete utilizing Scanning Electron Microscope (SEM) in order to identify possible effects on the ITZ related to different recipes and production parameters. SEM is
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Closed-Loop Autofocus Scheme for Scanning Electron Microscope
Directory of Open Access Journals (Sweden)
Cui Le
2015-01-01
Full Text Available In this paper, we present a full scale autofocus approach for scanning electron microscope (SEM. The optimal focus (in-focus position of the microscope is achieved by maximizing the image sharpness using a vision-based closed-loop control scheme. An iterative optimization algorithm has been designed using the sharpness score derived from image gradient information. The proposed method has been implemented and validated using a tungsten gun SEM at various experimental conditions like varying raster scan speed, magnification at real-time. We demonstrate that the proposed autofocus technique is accurate, robust and fast.
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Optimization study of direct morphology observation by cold field emission SEM without gold coating.
He, Dan; Fu, Cheng; Xue, Zhigang
2018-06-01
Gold coating is a general operation that is generally applied on non-conductive or low conductive materials, during which the morphology of the materials can be examined by scanning electron microscopy (SEM). However, fatal deficiencies in the materials can result in irreversible distortion and damage. The present study directly characterized different low conductive materials such as hydroxyapatite, modified poly(vinylidene fluoride) (PVDF) fiber, and zinc oxide nanopillar by cold field emission scanning electron microscopy (FE-SEM) without a gold coating. According to the characteristics of the low conductive materials, various test conditions, such as different working signal modes, accelerating voltages, electron beam spots, and working distances, were characterized to determine the best morphological observations of each sample. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Sisti, Karin Ellen
2011-01-01
Objetivo: Estudar a topografia a osseointegração de implantes de titânio sob ação do LASER de alta intensidade com e sem deposição química de hidroxiapatita, em coelhos. Método: Foram utilizados 30 coelhos albinos que receberam em suas tíbias 3 tipos de superfície de implantes: grupo controle(GI) implantes usinados, grupo(GII) irradiado LASER(Yb), e grupo irradiado e depositado hidroxiapatita pelo método biomimético(GIII). Após os períodos de avaliações (30 e 60 dias) os implantes foram subme...
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Arndt, J; Deboudt, K; Anderson, A; Blondel, A; Eliet, S; Flament, P; Fourmentin, M; Healy, R M; Savary, V; Setyan, A; Wenger, J C
2016-03-01
The chemical composition of single particles deposited on industrial filters located in three different chimneys of an iron-manganese (Fe-Mn) alloy manufacturing plant have been compared using aerosol time-of-flight mass spectrometry (ATOFMS) and scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX). Very similar types of particles were observed using both analytical techniques. Calcium-containing particles dominated in the firing area of the sintering unit, Mn and/or Al-bearing particles were observed at the cooling area of the sintering unit, while Mn-containing particles were dominant at the smelting unit. SEM-EDX analysis of particles collected downstream of the industrial filters showed that the composition of the particles emitted from the chimneys is very similar to those collected on the filters. ATOFMS analysis of ore samples was also performed to identify particulate emissions that could be generated by wind erosion and manual activities. Specific particle types have been identified for each emission source (chimneys and ore piles) and can be used as tracers for source apportionment of ambient PM measured in the vicinity of the industrial site. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Characterization of some biological specimens using TEM and SEM
Ghosh, Nabarun; Smith, Don W.
2009-05-01
The advent of novel techniques using the Transmission and Scanning Electron Microscopes improved observation on various biological specimens to characterize them. We studied some biological specimens using Transmission and Scanning Electron Microscopes. We followed negative staining technique with Phosphotungstic acid using bacterial culture of Bacillus subtilis. Negative staining is very convenient technique to view the structural morphology of different samples including bacteria, phage viruses and filaments in a cell. We could observe the bacterial cell wall and flagellum very well when trapped the negative stained biofilm from bacterial culture on a TEM grid. We cut ultra thin sections from the fixed root tips of Pisum sativum (Garden pea). Root tips were pre fixed with osmium tetroxide and post fixed with uranium acetate and placed in the BEEM capsule for block making. The ultrathin sections on the grid under TEM showed the granular chromatin in the nucleus. The protein bodies and large vacuoles with the storage materials were conspicuous. We followed fixation, critical point drying and sputter coating with gold to view the tissues with SEM after placing on stubs. SEM view of the leaf surface of a dangerous weed Tragia hispida showed the surface trichomes. These trichomes when break on touching releases poisonous content causing skin irritation. The cultured tissue from in vitro culture of Albizia lebbeck, a tree revealed the regenerative structures including leaf buds and stomata on the tissue surface. SEM and TEM allow investigating the minute details characteristic morphological features that can be used for classroom teaching.
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Does your SEM really tell the truth?--How would you know? Part 1.
Postek, Michael T; Vladár, András E
2013-01-01
The scanning electron microscope (SEM) has gone through a tremendous evolution to become a critical tool for many and diverse scientific and industrial applications. The high resolution of the SEM is especially suited for both qualitative and quantitative applications especially for nanotechnology and nanomanufacturing. Quantitatively, measurement, or metrology is one of the main uses. It is likely that one of the first questions asked before even the first scanning electron micrograph was ever recorded was: "… how big is that?" The quality of that answer has improved a great deal over the past few years especially since today these instruments are being used as a primary measurement tool on semiconductor processing lines to monitor the manufacturing processes. The well-articulated needs of semiconductor production prompted a rapid evolution of the instrument and its capabilities. Over the past 20 years or so, instrument manufacturers, through substantial semiconductor industry investment of research and development (R&D) money, have vastly improved the performance of these instruments. All users have benefited from this investment, especially where quantitative measurements with an SEM are concerned. But, how good are these data? This article discusses some of the most important aspects and larger issues associated with imaging and measurements with the SEM that every user should know, and understand before any critical quantitative work is attempted. © Wiley Periodicals, Inc.
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New Scanning Electron Microscope Used for Cryogenic Tensile Testing
Maximilien Brice
2013-01-01
At CERN engineering department's installation for cryogenic tensile testing, the new scanning electron microscope (SEM) allows for detailed optical observations to be carried out. Using the SEM, surface coatings and tensile properties of materials can investigated in order to better understand how they behave under different conditions.
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Depoimento sem dano: a escuta da psicanálise ou a escuta do direito?
Directory of Open Access Journals (Sweden)
Conte, Bárbara de Souza
2008-01-01
Full Text Available O depoimento sem dano é uma prática de inquirição de crianças supostamente vitimas de abuso sexual, que está sendo introduzido no Poder Judiciário, onde o inquérito é realizado por psicólogo. Problematizo, em um primento ponto, a verdade do discurso produzido pela criança em uma situação de depoimento, buscando discutir o que se chama em psicanálise de verdade histórico - vivencial a partir do traumático do acontecimento e suas consequëncias psíquicas. Em um segundo ponto, interrogo sobre a certeza da prova e as formas de escuta e intervenção desde uma perspectiva ética do fazer do psicólogo
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In Situ Characterization of Boehmite Particles in Water Using Liquid SEM.
Yao, Juan; Arey, Bruce W; Yang, Li; Zhang, Fei; Komorek, Rachel; Chun, Jaehun; Yu, Xiao-Ying
2017-09-27
In situ imaging and elemental analysis of boehmite (AlOOH) particles in water is realized using the System for Analysis at the Liquid Vacuum Interface (SALVI) and Scanning Electron Microscopy (SEM). This paper describes the method and key steps in integrating the vacuum compatible SAVLI to SEM and obtaining secondary electron (SE) images of particles in liquid in high vacuum. Energy dispersive x-ray spectroscopy (EDX) is used to obtain elemental analysis of particles in liquid and control samples including deionized (DI) water only and an empty channel as well. Synthesized boehmite (AlOOH) particles suspended in liquid are used as a model in the liquid SEM illustration. The results demonstrate that the particles can be imaged in the SE mode with good resolution (i.e., 400 nm). The AlOOH EDX spectrum shows significant signal from the aluminum (Al) when compared with the DI water and the empty channel control. In situ liquid SEM is a powerful technique to study particles in liquid with many exciting applications. This procedure aims to provide technical know-how in order to conduct liquid SEM imaging and EDX analysis using SALVI and to reduce potential pitfalls when using this approach.
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Katsen-Globa, Alisa; Puetz, Norbert; Gepp, Michael M; Neubauer, Julia C; Zimmermann, Heiko
2016-11-01
One of the often reported artefacts during cell preparation to scanning electron microscopy (SEM) is the shrinkage of cellular objects, that mostly occurs at a certain time-dependent stage of cell drying. Various methods of drying for SEM, such as critical point drying, freeze-drying, as well as hexamethyldisilazane (HMDS)-drying, were usually used. The latter becomes popular since it is a low cost and fast method. However, the correlation of drying duration and real shrinkage of objects was not investigated yet. In this paper, cell shrinkage at each stage of preparation for SEM was studied. We introduce a shrinkage coefficient using correlative light microscopy (LM) and SEM of the same human mesenchymal stem cells (hMSCs). The influence of HMDS-drying duration on the cell shrinkage is shown: the longer drying duration, the more shrinkage is observed. Furthermore, it was demonstrated that cell shrinkage is inversely proportional to cultivation time: the longer cultivation time, the more cell spreading area and the less cell shrinkage. Our results can be applicable for an exact SEM quantification of cell size and determination of cell spreading area in engineering of artificial cellular environments using biomaterials. SCANNING 38:625-633, 2016. © 2016 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.
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Hein, L R O; Campos, K A; Caltabiano, P C R O; Kostov, K G
2013-01-01
The methodology for fracture analysis of polymeric composites with scanning electron microscopes (SEM) is still under discussion. Many authors prefer to use sputter coating with a conductive material instead of applying low-voltage (LV) or variable-pressure (VP) methods, which preserves the original surfaces. The present work examines the effects of sputter coating with 25 nm of gold on the topography of carbon-epoxy composites fracture surfaces, using an atomic force microscope. Also, the influence of SEM imaging parameters on fractal measurements is evaluated for the VP-SEM and LV-SEM methods. It was observed that topographic measurements were not significantly affected by the gold coating at tested scale. Moreover, changes on SEM setup leads to nonlinear outcome on texture parameters, such as fractal dimension and entropy values. For VP-SEM or LV-SEM, fractal dimension and entropy values did not present any evident relation with image quality parameters, but the resolution must be optimized with imaging setup, accompanied by charge neutralization. © Wiley Periodicals, Inc.
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International Nuclear Information System (INIS)
Arndt, J.; Deboudt, K.; Anderson, A.; Blondel, A.; Eliet, S.; Flament, P.; Fourmentin, M.; Healy, R.M.; Savary, V.; Setyan, A.; Wenger, J.C.
2016-01-01
The chemical composition of single particles deposited on industrial filters located in three different chimneys of an iron-manganese (Fe–Mn) alloy manufacturing plant have been compared using aerosol time-of-flight mass spectrometry (ATOFMS) and scanning electron microscopy–energy dispersive X-ray spectrometry (SEM-EDX). Very similar types of particles were observed using both analytical techniques. Calcium-containing particles dominated in the firing area of the sintering unit, Mn and/or Al-bearing particles were observed at the cooling area of the sintering unit, while Mn-containing particles were dominant at the smelting unit. SEM-EDX analysis of particles collected downstream of the industrial filters showed that the composition of the particles emitted from the chimneys is very similar to those collected on the filters. ATOFMS analysis of ore samples was also performed to identify particulate emissions that could be generated by wind erosion and manual activities. Specific particle types have been identified for each emission source (chimneys and ore piles) and can be used as tracers for source apportionment of ambient PM measured in the vicinity of the industrial site. - Highlights: • Similar composition for emitted particles as those collected on the chimney filters. • Emitted particles dominated by Ca-, Mn and/or Al-containing particles. • Identification of specific particle types emitted by the different process units. - The particles emitted by metallurgy activities are fully described by ATOFMS and SEM-EDX, enabling the identification of specific particle types from the different units of the process.
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Characteristics of different frequency ranges in scanning electron microscope images
International Nuclear Information System (INIS)
Sim, K. S.; Nia, M. E.; Tan, T. L.; Tso, C. P.; Ee, C. S.
2015-01-01
We demonstrate a new approach to characterize the frequency range in general scanning electron microscope (SEM) images. First, pure frequency images are generated from low frequency to high frequency, and then, the magnification of each type of frequency image is implemented. By comparing the edge percentage of the SEM image to the self-generated frequency images, we can define the frequency ranges of the SEM images. Characterization of frequency ranges of SEM images benefits further processing and analysis of those SEM images, such as in noise filtering and contrast enhancement
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Characteristics of different frequency ranges in scanning electron microscope images
Energy Technology Data Exchange (ETDEWEB)
Sim, K. S., E-mail: kssim@mmu.edu.my; Nia, M. E.; Tan, T. L.; Tso, C. P.; Ee, C. S. [Faculty of Engineering and Technology, Multimedia University, 75450 Melaka (Malaysia)
2015-07-22
We demonstrate a new approach to characterize the frequency range in general scanning electron microscope (SEM) images. First, pure frequency images are generated from low frequency to high frequency, and then, the magnification of each type of frequency image is implemented. By comparing the edge percentage of the SEM image to the self-generated frequency images, we can define the frequency ranges of the SEM images. Characterization of frequency ranges of SEM images benefits further processing and analysis of those SEM images, such as in noise filtering and contrast enhancement.
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SEM observations of particle track membrane surfaces modificated using plasma treatment
International Nuclear Information System (INIS)
Sartowska, B.; Buczkowski, M.; Starosta, W.
2003-01-01
This work presents results of scanning electron microscopy (SEM) observations of 0.4 μm membranes after plasma treatment with different parameters. The morphology changes at the surfaces and at the pore walls were observed. The character of changes in the membrane parameters according to the process conditions was determined
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Directory of Open Access Journals (Sweden)
José Glauco LOBO FILHO
2002-09-01
Full Text Available INTRODUÇÃO: A circulação extracorpórea (CEC e o manuseio da aorta ascendente (MAA estão associados a alta incidência de acidente vascular cerebral (AVC na cirurgia de revascularização do miocárdio (RM em pacientes idosos. Esta complicação deve-se, sobretudo, ao MAA, por ocasião do pinçamento e despinçamento, quer para isolamento do coração do circuito de CEC, quer para realização das anastomoses dos enxertos na aorta ascendente. OBJETIVOS: Verificar mortalidades imediata e a médio prazo e a ocorrência de AVC no pós-operatório imediato (POI em pacientes acima de 75 anos submetidos a cirurgia de revascularização do sistema coronariano esquerdo (SCE, sem CEC e sem MAA. MÉTODO: De janeiro de 2000 a abril de 2002, 40 pacientes acima de 75 anos (média 79,1 anos foram submetidos a cirurgia de revascularização do SCE, com enxerto de artéria torácica interna esquerda (ATIE para a artéria descendente anterior (DA, e enxerto(s de veia safena magna oriundo(s da ATIE para outro(s ramo(s da coronária esquerda (enxerto composto, sem CEC e sem MAA. Houve predominância do sexo masculino (67,5%. Foram realizados 89 enxertos (média 2,22 pontes por paciente, sendo 40 (44,94% de ATIE e 49 (55,06% de veia safena. A ocorrência de AVC foi avaliada por exames clínico e neurológico. RESULTADOS: Não foi observada ocorrência de AVC no grupo estudado. Não houve óbitos no POI. CONCLUSÃO: A cirurgia de revascularização do SCE em pacientes acima de 75 anos sem CEC e sem MAA pode ser realizada sistematicamente de modo a evitar a ocorrência de AVC, com baixa mortalidade.INTRODUCTION: Cardiopulmonary bypass (CPB and Ascending Aorta manipulation (AAM are associated with a high incidence of stroke in coronary surgery in patients older than 75 years. This complication is due, mostly, to the handling of the aorta by the time of the cross-clamping, either for heart isolation from CPB, or to perform saphenous vein graft anastomosis to the
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FIB-SEM cathodoluminescence tomography: practical and theoretical considerations.
De Winter, D A M; Lebbink, M N; Wiggers De Vries, D F; Post, J A; Drury, M R
2011-09-01
Focused ion beam-scanning electron microscope (FIB-SEM) tomography is a powerful application in obtaining three-dimensional (3D) information. The FIB creates a cross section and subsequently removes thin slices. The SEM takes images using secondary or backscattered electrons, or maps every slice using X-rays and/or electron backscatter diffraction patterns. The objective of this study is to assess the possibilities of combining FIB-SEM tomography with cathodoluminescence (CL) imaging. The intensity of CL emission is related to variations in defect or impurity concentrations. A potential problem with FIB-SEM CL tomography is that ion milling may change the defect state of the material and the CL emission. In addition the conventional tilted sample geometry used in FIB-SEM tomography is not compatible with conventional CL detectors. Here we examine the influence of the FIB on CL emission in natural diamond and the feasibility of FIB-SEM CL tomography. A systematic investigation establishes that the ion beam influences CL emission of diamond, with a dependency on both the ion beam and electron beam acceleration voltage. CL emission in natural diamond is enhanced particularly at low ion beam and electron beam voltages. This enhancement of the CL emission can be partly explained by an increase in surface defects induced by ion milling. CL emission enhancement could be used to improve the CL image quality. To conduct FIB-SEM CL tomography, a recently developed novel specimen geometry is adopted to enable sequential ion milling and CL imaging on an untilted sample. We show that CL imaging can be manually combined with FIB-SEM tomography with a modified protocol for 3D microstructure reconstruction. In principle, automated FIB-SEM CL tomography should be feasible, provided that dedicated CL detectors are developed that allow subsequent milling and CL imaging without manual intervention, as the current CL detector needs to be manually retracted before a slice can be milled
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Directory of Open Access Journals (Sweden)
Bruno Botelho PINHEIRO
2002-09-01
Full Text Available MÉTODO: No período de agosto de 1997 a maio de 2001, 250 pacientes multiarteriais, consecutivos, foram submetidos à cirurgia de revascularização do miocárdio sem circulação extracorpórea. A faixa etária dos pacientes variou de 38 a 83 anos (média de 59,9 anos, dos quais 62% eram do sexo masculino. A principal indicação cirúrgica foi a insuficiência coronariana crônica (82%. Todos os pacientes foram operados por esternotomia mediana. RESULTADOS: Três (1,2% pacientes necessitaram de instalação de circulação extracorpórea. Nos demais 247 pacientes, realizou-se 592 anastomoses, com uma média de 2,4 pontes/paciente. A artéria torácica interna esquerda foi utilizada em 198 (80,1% pacientes, a artéria torácica interna direita em 5 (2% pacientes e a veia safena em 247 (100% pacientes. As artérias coronárias mais revascularizadas foram o ramo interventricular anterior (89% e o ramo marginal esquerdo (53%. A mortalidade hospitalar global foi de 4%, sendo a principal causa o infarto pós-operatório (1,2%. Morbidade pós-operatória foi constatada em 23 (9,3% pacientes. O tempo médio de permanência hospitalar foi de 7,7 dias. CONCLUSÃO: Conclui-se da presente investigação, que a revascularização do miocárdio sem circulação extracorpórea em pacientes multiarteriais é factível, reprodutível e com baixo índice de complicações pós-operatórias.METHODS: From August 1997 to May 2001, off-pump coronary artery bypass grafting (OPCAB was performed in 250 consecutive patients with multivessel disease. Ages ranged from 38 to 83 years (mean-age 59.9 years and 62% of the patients were males. The main surgical indication was chronic coronary insufficiency (82%. The surgical approach was through median sternotomy in all patients. RESULTS: Three (1.2% patients needed cardiopulmonary bypass support. In the 247 remaining patients, we performed 592 grafts (mean 2.4 grafts/patient. The left internal thoracic artery was used in
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Development of an Economical Interfacing Circuit for Upgrading of SEM Data Printing System
International Nuclear Information System (INIS)
Punnachaiya, S.; Thong-Aram, D.
2002-01-01
The operating conditions of a Scanning Electron Microscope (SEM) i.e., magnification, accelerating voltage, micron mark and film identification labeling, are very important for the accurate interpretation of a micrograph picture. In the old model SEM, the built-in data printing system for film identification can be inputted only the numerical number. This will be made a confusing problems when various operating conditions were applied in routine work. An economical interfacing circuit, therefore, was developed to upgrade the data printing system for capable of alphanumerical labeling. The developed circuit was tested on both data printing systems of JSM-T220 and JSM-T330 (JEOL SEM). It was found that the interfacing function worked properly and easily installed
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Directory of Open Access Journals (Sweden)
Yuangang Zu
2012-07-01
Full Text Available An ultrasound and microwave assisted alternant extraction method (UMAE was applied for extracting dihydroquercetin (DHQ from <em>Larix gmeliniem>i> wood. This investigation was conducted using 60% ethanol as solvent, 1:12 solid to liquid ratio, and 3 h soaking time. The optimum treatment time was ultrasound 40 min, microwave 20 min, respectively, and the extraction was performed once. Under the optimized conditions, satisfactory extraction yield of the target analyte was obtained. Relative to ultrasound-assisted or microwave-assisted method, the proposed approach provides higher extraction yield. The effect of DHQ of different concentrations and synthetic antioxidants on oxidative stability in soy bean oil stored for 20 days at different temperatures (25 °C and 60 °C was compared. DHQ was more effective in restraining soy bean oil oxidation, and a dose-response relationship was observed. The antioxidant activity of DHQ was a little stronger than that of BHA and BHT. Soy bean oil supplemented with 0.08 mg/g DHQ exhibited favorable antioxidant effects and is preferable for effectively avoiding oxidation. The <em>L. gmeliniiem> wood samples before and after extraction were characterized by scanning electron microscopy. The results showed that the UMAE method is a simple and efficient technique for sample preparation.
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Directory of Open Access Journals (Sweden)
Luis Vinatea
2009-05-01
Full Text Available This work aimed at determining the dissolved oxygen consumption rate of Litopenaeus vannamei juveniles maintained in a microbial biofloc raceway system at high density with no aeration. Three 4 L bottles were filled for each treatment, sealed hermetically, and placed in an enclosed greenhouse raceway system. Four shrimp (13.2±1.42 g were assigned to two sets of the bottles, which underwent the following treatments: light conditions with no shrimp; dark conditions with no shrimp; light conditions with shrimp; and dark conditions with shrimp. Dissolved oxygen content was measured every 10 min for 30 min. A quadratic behavior was observed in dissolved oxygen concentration over time. Significant differences for oxigen consumption were observed only at 10 and 20 min between shrimp maintained in the dark and those under light conditions. At 10 min, a higher value was observed in shrimp maintained under light, and at 20 min, in the dark. Significant differences between 10 and 20 min and between 10 and 30 min were observed when oxygen consumption was analyzed over time in the presence of light. Under dark conditions there were significant differences only between 20 and 30 min. Lethal oxygen concentration (0.65 mg L-1 would be reached in less than one hour either under light or dark conditions with no aeration.O objetivo deste trabalho foi determinar o consumo de oxigênio dissolvido (OD de juvenis de Litopenaeus vannamei mantidos em sistema de cultivo de bioflocs bacterianos em alta densidade e ausência de aeração. Três garrafas de 4 L foram preenchidas para cada tratamento, fechadas hermeticamente e colocadas em sistema de cultivo fechado. Quatro camarões (13,2±1,42 g foram colocados em dois dos conjuntos de garrafas. Os tratamentos aplicados foram: luminosidade, sem camarões; escuro, sem camarões; luminosidade, com camarões; escuro, com camarões. A concentração de oxigênio dissolvido foi determinada a cada 10 min durante 30 min. Foi
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Schönherr, Holger; Schaeben, H.; Vancso, Gyula J.
1998-01-01
The mechanism of friction deposition of polytetrafluoroethylene (PTFE) and polyethylene (PE) was studied by scanning electron (SEM) and scanning force microscopy (SFM) on the worn surfaces of PTFE and PE sliders that were used in friction deposition on glass substrates. These surfaces exhibited a
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Pré-resfriamento em água de lichia 'B3' mantida em armazenamento refrigerado
del Aguila,Juan Saavedra; Hofman,Peter; Campbell,Terrence; Marques,José Roberto; Heiffig-del Aguila,Lília Sichmann; Kluge,Ricardo Alfredo
2009-01-01
Este experimento visou a estudar o efeito de diferentes temperaturas e tempos de pré-resfriamento em água sobre a qualidade de lichias 'B3', após a frigoconservação. Os tratamentos foram: T1 = controle (sem pré-resfriamento); T2 = imersão por cinco minutos em água a 2,5°C; T3 = imersão por 10 minutos em água a 2,5°C; T4 = imersão por 20 minutos em água a 2,5°C; T5 = imersão por sete minutos em água a 6°C; T6 = imersão por 20 minutos em água a 8°C e T7 = imersão por 10 minu...
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Directory of Open Access Journals (Sweden)
Jordana Costa Soares
2006-02-01
Full Text Available A sensibilização auditiva, ferramenta utilizada na pesquisa dos reflexos acústicos, provoca a redução do limiar de reflexo acústico a partir de um estímulo facilitador, que pode ser apresentado antes ou simultaneamente ao tom eliciador do reflexo acústico. São comparados os limiares pré e pósexposição ao estímulo, esperando-se obter a redução do limiar. A partir do estudo dos reflexos acústicos é possível obter maiores informações a respeito das vias auditivas, como estruturas do tronco encefálico, visto que o arco reflexo está relacionado a núcleos auditivos nessa região. Eles também estão envolvidos no processamento auditivo. Assim, alterações do reflexo acústico poderiam estar relacionadas a falhas em habilidades de processamento auditivo. OBJETIVO: Esta pesquisa teve o objetivo de estudar a sensibilização do reflexo acústico a partir de um estímulo facilitador de 6 kHz em neonatos nascidos a termo, sem risco para alteração auditiva. RESULTADOS: Foi encontrada redução significativa do limiar de reflexo acústico para todas as freqüências pesquisadas em ambos os sexos. CONCLUSÃO: A apresentação simultânea de um estímulo facilitador de alta freqüência gera redução do limiar de reflexo acústico em neonatos sem risco para perda auditiva.The auditory sensitization, a tool used in the investigation of acoustic reflex, allows the decrease of acoustic reflex thresholds from a facilitating stimulus. It may be presented before or simultaneously with the elicitor tone. The thresholds after and before the facilitating stimulus are compared and it is expected to see the decreased threshold. From the study of the acoustic reflex it is possible to obtain information about the auditory pathways, such as structures of the brainstem, since the acoustic reflex pathway is related to the auditory nuclei in this site. They are also involved in auditory processing. Thus, alterations of the acoustic reflex could be
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International Nuclear Information System (INIS)
Tonny Anak Lanyau; Yusof Abdullah; Tom, P.P.
2011-01-01
Reactor TRIGA PUSPATI (RTP) is the only nuclear research reactor in Malaysia. Since the first criticality on 28th June 1982, RTP has been going through the safe operation and well maintenance. Along the period of operation almost 30 years, some of the reactor system and component has been refurbished, upgraded and replaced to ensure the functionality and safety to the reactor itself as well as to protect personnel and environment. Primary cooling system is to provide the sufficient cooling to the reactor by removal of the heat generated in the reactor core through the heat transfer process in the heat exchanger. In 2009, RTP has been undergoing the primary cooling system upgrades. Primary cooling system components including aluminium pipes has been dismantled and replaced with the new system. As a part of the ageing management programme and radiation damage study, the disposed aluminum pipes were taken and used in this study. Scanning Electron Microscope (SEM) is used to study the surface topography and elemental composition in conjunction of energy dispersive x-ray spectroscopy analysis. This paper presents the study that has been conducted. (author)
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Directory of Open Access Journals (Sweden)
Igor Lins Lemos
2015-03-01
Full Text Available Objetivo Avaliar a equivalência semântica e a consistência interna da Game Addiction Scale (GAS: versão em português. Métodos O procedimento constituiu-se das seguintes etapas: a revisão da literatura; b tradução do instrumento original; c retrotradução; d revisão técnica e avaliação da compreensão verbal, realizada por profissionais da área da saúde; e avaliação da compreensão verbal do instrumento, por uma amostra de estudantes; f análise da consistência interna (alfa de Cronbach. Os participantes, com exceção dos especialistas, foram selecionados por conveniência. A participação dos sujeitos foi diferente em cada fase: tradutores (n = 2, retrotradução (n = 1, revisão técnica (n = 2, especialistas (n = 12, pré-teste com estudantes universitários (n = 40 e mensuração com estudantes universitários (n = 100. Resultados Poucas alterações semânticas de expressões e termos foram realizadas para adaptar-se à cultura-alvo. O nível de compreensão verbal dos participantes (especialistas e estudantes foi superior a 90% e a análise do alfa de Cronbach correspondeu a 0,92 para todo o instrumento. Conclusão A Escala de Dependência de Jogos Eletrônicos (ESDEJE foi submetida a tradução e adaptação para o idioma português (do Brasil, apresentando consistência interna adequada. Ademais, sugere-se a realização do processo de validação referente à equivalência de mensuração e reprodutibilidade do instrumento.
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Comportamento do meloeiro em cultivo sem solo com a utilização de biofertilizante
Directory of Open Access Journals (Sweden)
Villela Junior Luiz Vitor E.
2003-01-01
Full Text Available O reaproveitamento de nutrientes após a fermentação de resíduos orgânicos em biodigestor, associado à técnica do cultivo hidropônico, é uma alternativa para reduzir custos na agricultura, além de contribuir no menor consumo das reservas naturais de nutrientes do planeta. Com esse enfoque, estudou-se o comportamento da cultura do meloeiro usando a técnica hidropônica e efluente de biodigestor proveniente da fermentação anaeróbica de estrume bovino. Cultivou-se o meloeiro (Cucumis melo L. 'Bônus 2' em condições de ambiente protegido. O delineamento estatístico utilizado foi de blocos casualizados, com 4 tratamentos (cultivo hidropônico em sistema fechado tipo NFT com uso de solução nutritiva organo-mineral; cultivo hidropônico em sistema fechado tipo NFT com uso de solução nutritiva 100% mineral; cultivo em sistema aberto, com substrato e solução nutritiva organo-mineral e cultivo em sistema aberto, com substrato e solução nutritiva 100% mineral e 6 repetições. Foram realizadas avaliações quanto a altura de plantas aos 50; 56; 63; 70 e 77 dias após a semeadura; tempo de colheita; peso de frutos e produtividade. As melhores respostas foram observadas no cultivo hidropônico em sistema fechado tipo NFT com uso de solução nutritiva 100% mineral. A substituição parcial de adubos minerais por biofertilizante, se mostrou viável para os tratamentos em sistema aberto (com substrato, constituindo-se em masi uma alternativa aos horticultores.
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Artérias e veias placentárias em ovinos deslanados sem raça definida (Ovis aries, L. 1758
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Janicleide Maria de Almeida
2000-01-01
Full Text Available O suprimento sangüíneo da placenta de 30 ovelhas deslanadas sem raça definida foi estudado mediante análise de peças obtidas através de injeção vascular com Látex Neoprene 650 corado. Constataram-se no material casos de gestações únicas (53,3%, gemelares (46,7% e trigemelares (3,3%. Em todos os casos analisados, observaram-se 4 vasos umbilicais (2 artérias e 2 veias além do ducto alantóide, na constituição do funículo umbilical. Em apenas 1 caso (gestação trigemelar, as duas artérias umbilicais de um dos fetos fundiram-se na porção média do funículo umbilical, e neste caso integrava apenas uma veia umbilical. A área placentária hilar variava de 2,0 a 6,0 centímetros dependendo da fase de gestação. O número médio de placentônios por gestação foi igual a 96, com tamanhos e formas bastante diversificados, sendo que aqueles maiores que 1,5 centímetro eram predominantes, assim como aqueles de formato ovóide. Os placentônios eram irrigados e drenados por uma série diversificada de artérias e veias, constituindo arranjos arteriocotiledonários e venocotiledonários, perfazendo um total de 299 e 314 arranjos respectivamente.
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Marginal adaptation of a low-shrinkage silorane-based composite: A SEM-analysis
DEFF Research Database (Denmark)
Schmidt, Malene; Bindslev, Preben Hørsted; Poulsen, Sven
2012-01-01
shrinkage, has been marketed. Objective. To investigate whether reduced polymerization shrinkage improves the marginal adaptation of composite restorations. Material and methods. A total of 156 scanning electron microscopy (SEM) pictures (78 baseline, 78 follow-up) of the occlusal part of Class II......-casts of the restorations were used for SEM pictures at x 16 magnification. Pictures from baseline and follow-up (398 days, SD 29 days) were randomized and the examiner was blinded to the material and the age of the restoration. Stereologic measurements were used to calculate the length and the width of the marginal...
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Suzuki, Kazuhiko; Oho, Eisaku
2013-01-01
Quality of a scanning electron microscopy (SEM) image is strongly influenced by noise. This is a fundamental drawback of the SEM instrument. Complex hysteresis smoothing (CHS) has been previously developed for noise removal of SEM images. This noise removal is performed by monitoring and processing properly the amplitude of the SEM signal. As it stands now, CHS may not be so utilized, though it has several advantages for SEM. For example, the resolution of image processed by CHS is basically equal to that of the original image. In order to find wide application of the CHS method in microscopy, the feature of CHS, which has not been so clarified until now is evaluated correctly. As the application of the result obtained by the feature evaluation, cursor width (CW), which is the sole processing parameter of CHS, is determined more properly using standard deviation of noise Nσ. In addition, disadvantage that CHS cannot remove the noise with excessively large amplitude is improved by a certain postprocessing. CHS is successfully applicable to SEM images with various noise amplitudes. © Wiley Periodicals, Inc.
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Simulation study of secondary electron images in scanning ion microscopy
Ohya, K
2003-01-01
The target atomic number, Z sub 2 , dependence of secondary electron yield is simulated by applying a Monte Carlo code for 17 species of metals bombarded by Ga ions and electrons in order to study the contrast difference between scanning ion microscopes (SIM) and scanning electron microscopes (SEM). In addition to the remarkable reversal of the Z sub 2 dependence between the Ga ion and electron bombardment, a fine structure, which is correlated to the density of the conduction band electrons in the metal, is calculated for both. The brightness changes of the secondary electron images in SIM and SEM are simulated using Au and Al surfaces adjacent to each other. The results indicate that the image contrast in SIM is much more sensitive to the material species and is clearer than that for SEM. The origin of the difference between SIM and SEM comes from the difference in the lateral distribution of secondary electrons excited within the escape depth.
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PAT and SEM study of porous silicon formed by anodization methods
International Nuclear Information System (INIS)
Liu Jian; Wei Long; Wang Huiyao; Ma Chuangxin; Wang Baoyi
2000-01-01
The porous silicon formed by anodization of crystal silicon was studied by positron annihilation technique (PAT) and scanning electron microscopy (SEM). The PAT experiments showed that the mean life and vacancy defects increased with the increasing anodization time. While the intensities of the longest lifetime, several ns-tens ns (ortho-positronium) dropped down. Small single-crystal Si spheres with mean radius of a few μm were observed by SEM after anodization. Pits with mean radius of a few μm from the divorcement of single-crystal spheres were also observed after further anodization. The increases of vacancy defects might be that the extension of structures of porous silicon towards inner layer with anodization time and caused more vacancy defects in inner layer. The SEM observation presented another possibility of the increase of density of vacancy defects in surface layer induced by the change of structures
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Mapping the Complex Morphology of Cell Interactions with Nanowire Substrates Using FIB-SEM
DEFF Research Database (Denmark)
Wierzbicki, Rafal; Købler, Carsten; Jensen, Mikkel Ravn Boye
2013-01-01
Using high resolution focused ion beam scanning electron microscopy (FIB-SEM) we study the details of cell-nanostructure interactions using serial block face imaging. 3T3 Fibroblast cellular monolayers are cultured on flat glass as a control surface and on two types of nanostructured scaffold...... substrates made from silicon black (Nanograss) with low- and high nanowire density. After culturing for 72 hours the cells were fixed, heavy metal stained, embedded in resin, and processed with FIB-SEM block face imaging without removing the substrate. The sample preparation procedure, image acquisition...
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Nanomanufacturing Concerns about Measurements Made in the SEM Part IV: Charging and its Mitigation.
Postek, Michael T; Vladár, András E
2015-01-01
This is the fourth part of a series of tutorial papers discussing various causes of measurement uncertainty in scanned particle beam instruments, and some of the solutions researched and developed at NIST and other research institutions. Scanned particle beam instruments especially the scanning electron microscope (SEM) have gone through tremendous evolution to become indispensable tools for many and diverse scientific and industrial applications. These improvements have significantly enhanced their performance and made them far easier to operate. But, the ease of operation has also fostered operator complacency. In addition, the user-friendliness has reduced the apparent need for extensive operator training. Unfortunately, this has led to the idea that the SEM is just another expensive "digital camera" or another peripheral device connected to a computer and that all of the problems in obtaining good quality images and data have been solved. Hence, one using these instruments may be lulled into thinking that all of the potential pitfalls have been fully eliminated and believing that, everything one sees on the micrograph is always correct. But, as described in this and the earlier papers, this may not be the case. Care must always be taken when reliable quantitative data are being sought. The first paper in this series discussed some of the issues related to signal generation in the SEM, including instrument calibration, electron beam-sample interactions and the need for physics-based modeling to understand the actual image formation mechanisms to properly interpret SEM images. The second paper has discussed another major issue confronting the microscopist: specimen contamination and methods to eliminate it. The third paper discussed mechanical vibration and stage drift and some useful solutions to mitigate the problems caused by them, and here, in this the fourth contribution, the issues related to specimen "charging" and its mitigation are discussed relative to
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Directory of Open Access Journals (Sweden)
Emilio Moyano Díaz
2012-12-01
Full Text Available Se busca identificar el significado de los conceptos 'terremoto' y 'maremoto' en dos grupos diferentemente expuestos al evento acaecido en Chile el 27/02/2010, en una muestra no probabilística intencional, compuesta por 240 personas provenientes de las ciudades de Constitución (n=104 - expuestas directamente al terremoto y maremoto -, y de Punta Arenas (n=136 expuestas vicariamente. Mediante redes semánticas naturales (R.S. construidas ad-hoc, fue observado que terremoto y tsunami tienen significados semejantes, relacionados al miedo, muerte, destrucción, desesperación, desastre, pérdida, angustia, tristeza, pena, dolor y pánico. Adicionalmente, aquellos que vivieron directamente el fenómeno utilizan más definidoras de tipo emocional al definir terremoto que aquellos que fueron expuestos a él de modo vicario.Procurou-se identificar o significado dos conceitos 'terremoto' e 'tsunami' em dois grupos diferentemente expostos ao evento acontecido no Chile em 27/02/2010, em uma amostra não-probabilística intencional, composta por 240 pessoas provenientes das cidades de Constitución (n=104, expostas diretamente ao terremoto e ao maremoto, e de Punta Arenas (n=136, expostas vicariamente. Pelas redes semânticas naturais (R.S. construídas ad hoc, foi observado que terremoto e tsunami têm significados semelhantes, relacionadas a medo, morte, destruição, desespero, desastre, perda, angústia, tristeza, pena, dor e pânico. Além disso, aqueles que experimentaram diretamente o fenômeno tendem a usar mais palavras de cunho emocional para definir terremoto, do que aqueles que foram expostos a ele vicariamen.The purpose of this research was to describe the meaning of "earthquake" and "tsunami" in two groups with different exposures to the Chilean natural disaster on February 27th, 2010. A non-probabilistic sample of two-hundred-forty subjects from Constitución (n=104 and Punta Arenas (n=136 was selected. The first group was directly exposed
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Multiplatform Mobile Laser Scanning: Usability and Performance
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Yuwei Chen
2012-08-01
Full Text Available Mobile laser scanning is an emerging technology capable of capturing three-dimensional data from surrounding objects. With state-of-the-art sensors, the achieved point clouds capture object details with good accuracy and precision. Many of the applications involve civil engineering in urban areas, as well as traffic and other urban planning, all of which serve to make 3D city modeling probably the fastest growing market segment in this field. This article outlines multiplatform mobile laser scanning solutions such as vehicle- and trolley-operated urban area data acquisition, and boat-mounted equipment for fluvial environments. Moreover, we introduce a novel backpack version of mobile laser scanning equipment for surveying applications in the field of natural sciences where the requirements include precision and mobility in variable terrain conditions. In addition to presenting a technical description of the systems, we discuss the performance of the solutions in the light of various applications in the fields of urban mapping and modeling, fluvial geomorphology, snow-cover characterization, precision agriculture, and in monitoring the effects of climate change on permafrost landforms. The data performance of the mobile laser scanning approach is described by the results of an evaluation of the ROAMER on a permanent MLS test field. Furthermore, an <em>in> <em>situ> accuracy assessment using a field of spherical 3D targets for the newly-introduced Akhka backpack system is conducted and reported on.
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Correlative SEM SERS for quantitative analysis of dimer nanoparticles.
Timmermans, F J; Lenferink, A T M; van Wolferen, H A G M; Otto, C
2016-11-14
A Raman microscope integrated with a scanning electron microscope was used to investigate plasmonic structures by correlative SEM-SERS analysis. The integrated Raman-SEM microscope combines high-resolution electron microscopy information with SERS signal enhancement from selected nanostructures with adsorbed Raman reporter molecules. Correlative analysis is performed for dimers of two gold nanospheres. Dimers were selected on the basis of SEM images from multi aggregate samples. The effect of the orientation of the dimer with respect to the polarization state of the laser light and the effect of the particle gap size on the Raman signal intensity is observed. Additionally, calculations are performed to simulate the electric near field enhancement. These simulations are based on the morphologies observed by electron microscopy. In this way the experiments are compared with the enhancement factor calculated with near field simulations and are subsequently used to quantify the SERS enhancement factor. Large differences between experimentally observed and calculated enhancement factors are regularly detected, a phenomenon caused by nanoscale differences between the real and 'simplified' simulated structures. Quantitative SERS experiments reveal the structure induced enhancement factor, ranging from ∼200 to ∼20 000, averaged over the full nanostructure surface. The results demonstrate correlative Raman-SEM microscopy for the quantitative analysis of plasmonic particles and structures, thus enabling a new analytical method in the field of SERS and plasmonics.
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Does your SEM really tell the truth? How would you know? part 3: vibration and drift
Postek, Michael T.; Vladár, András. E.; Cizmar, Petr
2014-09-01
This is the third of a series of papers discussing various causes of measurement uncertainty in scanned particle beam instruments, and some of the solutions researched and developed at NIST. Scanned particle beam instruments especially the scanning electron microscope (SEM) have gone through tremendous evolution to become indispensable tools for many and diverse scientifi c and industrial applications. These improvements have signifi cantly enhanced their performance and made them far easier to operate. But, ease of operation has also fostered operator complacency. In addition, the user-friendliness has reduced the need for extensive operator training. Unfortunately, this has led to the concept that the SEM is just another expensive digital camera or another peripheral device connected to a computer and that all of the issues related to obtaining quality data have been solved. Hence, a person (or company) using these instruments may be lulled into thinking that all of the potential pitfalls have been fully eliminated and they believe everything they see on the micrograph is always correct. But, as described in this and the earlier presentations this may not be the case. The fi rst paper in this series discussed some of the issues related to signal generation in the SEM, including instrument calibration, electron beam-sample interactions and the need for physics-based modelling to understand the actual image formation mechanisms to properly interpret SEM images. The second paper, discussed another major issue confronting the microscopist: specimen contamination and methods of contamination elimination. This third paper, discusses vibration and drift and some useful solutions.
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Scanning electron microscopy of primary bone tumors
International Nuclear Information System (INIS)
Pool, R.R.; Kerner, B.
1975-01-01
Critical-point-drying of tumor tissue fixed in a glutaraldehyde-paraformaldehyde solution and viewed by scanning electron microscopy (SEM) provides a 3-dimensional view of tumor cells and their matrices. This report describes the SEM appearance of three primary bone tumors: a canine osteosarcoma of the distal radius, a feline chondrosarcoma of the proximal tibia and a canine fibrosarcoma of the proximal humerus. The ultrastructural morphology is compared with the histologic appearance of each tumor
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Enhanced EDX images by fusion of multimodal SEM images using pansharpening techniques.
Franchi, G; Angulo, J; Moreaud, M; Sorbier, L
2018-01-01
The goal of this paper is to explore the potential interest of image fusion in the context of multimodal scanning electron microscope (SEM) imaging. In particular, we aim at merging the backscattered electron images that usually have a high spatial resolution but do not provide enough discriminative information to physically classify the nature of the sample, with energy-dispersive X-ray spectroscopy (EDX) images that have discriminative information but a lower spatial resolution. The produced images are named enhanced EDX. To achieve this goal, we have compared the results obtained with classical pansharpening techniques for image fusion with an original approach tailored for multimodal SEM fusion of information. Quantitative assessment is obtained by means of two SEM images and a simulated dataset produced by a software based on PENELOPE. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.
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Focusing on Environmental Biofilms With Variable-Pressure Scanning Electron Microscopy
Joubert, L.; Wolfaardt, G. M.; Du Plessis, K.
2006-12-01
Since the term biofilm has been coined almost 30 years ago, visualization has formed an integral part of investigations on microbial attachment. Electron microscopic (EM) biofilm studies, however, have been limited by the hydrated extracellular matrix which loses structural integrity with conventional preparative techniques, and under required high-vacuum conditions, resulting in a loss of information on spatial relationships and distribution of biofilm microbes. Recent advances in EM technology enable the application of Variable Pressure Scanning Electron Microscopy (VP SEM) to biofilms, allowing low vacuum and hydrated chamber atmosphere during visualization. Environmental biofilm samples can be viewed in situ, unfixed and fully hydrated, with application of gold-sputter-coating only, to increase image resolution. As the impact of microbial biofilms can be both hazardous and beneficial to man and his environment, recognition of biofilms as a natural form of microbial existence is needed to fully assess the potential role of microbial communities on technology. The integration of multiple techniques to elucidate biofilm processes has become imperative for unraveling complex phenotypic adaptations of this microbial lifestyle. We applied VP SEM as integrative technique with traditional and novel analytical techniques to (1)localize lignocellulosic microbial consortia applied for producing alternative bio-energy sources in the mining wastewater industry, (2) characterize and visualize wetland microbial communities in the treatment of winery wastewater, and (3)determine the impact of recombinant technology on yeast biofilm behavior. Visualization of microbial attachment to a lignocellulose substrate, and degradation of exposed plant tissue, gave insight into fiber degradation and volatile fatty acid production for biological sulphate removal from mining wastewater. Also, the 3D-architecture of complex biofilms developing in constructed wetlands was correlated with
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Scanning electron microscope - some aspects of the instrument and its applications
International Nuclear Information System (INIS)
Thatte, M.R.
1976-01-01
Development of the science of microscopy leading to three different types of microscopes - the optical, the conventional transmission electron microscope (CTEM) and the scanning electron microscope(SEM) has been discussed. Special advantages of the SEM in the solution of problems in industrial laboratories are mentioned. A brief reference to the latest instruments announced by Siemens AG shows the modern trends in the technique. A close similarity in image building between SEM and television is indicated. Operational anatomy of the SEM is reviewed. (author)
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A new clustering algorithm for scanning electron microscope images
Yousef, Amr; Duraisamy, Prakash; Karim, Mohammad
2016-04-01
A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning it with a focused beam of electrons. The electrons interact with the sample atoms, producing various signals that are collected by detectors. The gathered signals contain information about the sample's surface topography and composition. The electron beam is generally scanned in a raster scan pattern, and the beam's position is combined with the detected signal to produce an image. The most common configuration for an SEM produces a single value per pixel, with the results usually rendered as grayscale images. The captured images may be produced with insufficient brightness, anomalous contrast, jagged edges, and poor quality due to low signal-to-noise ratio, grained topography and poor surface details. The segmentation of the SEM images is a tackling problems in the presence of the previously mentioned distortions. In this paper, we are stressing on the clustering of these type of images. In that sense, we evaluate the performance of the well-known unsupervised clustering and classification techniques such as connectivity based clustering (hierarchical clustering), centroid-based clustering, distribution-based clustering and density-based clustering. Furthermore, we propose a new spatial fuzzy clustering technique that works efficiently on this type of images and compare its results against these regular techniques in terms of clustering validation metrics.
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Diego Spader de Souza; Rove Chishman
2017-01-01
O objetivo do presente artigo é tecer algumas considerações iniciais a respeito de uma proposta teórico-metodológica situada na interface entre a Semântica Cognitiva e a Lexicografia. Tal proposta, atualmente sendo desenvolvida em tese de doutorado, busca a aproximação entre a teoria da Semântica de Frames, de Charles J. Fillmore, com a onomasiologia e com a produção de dicionários onomasiológicos. A onomasiologia, tema de grande importância para a Semântica Estrutural, pode ser abordada, sob...
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Three dimensional imaging of surface geometry in SEM
International Nuclear Information System (INIS)
Slowko, W.
1997-01-01
A great advantage of scanning electron microscopy (SEM) is its ability of the surface topography in the way as a human eye is accustomed to see lights and shadows on macroobjects. However, SEM's can hardly display vertical dimensions of the structures. One of possible solutions is reconstruction of the surface profiles by directional detection of secondary electrons and proper signal processing. However, the surface profile still gives two dimensional information and the method should be extended to obtain fully three dimensional imaging. The extension consists in a simultaneous reconstruction of the surface profiles in two perpendicular directions (x and y) and their superposition. The solution proposed is based on a quadrupole detector system and a computer or analogue system for signal processing. Quantitative data of the surface topography can be displayed in many manners in the system of two or three co-ordinates with use of pseudo-colour for the altitude coding. (author)
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In-situ SEM microchip setup for electrochemical experiments with water based solutions
International Nuclear Information System (INIS)
Jensen, E.; Købler, C.; Jensen, P.S.; Mølhave, K.
2013-01-01
Studying electrochemical (EC) processes with electron microscopes offers the possibility of achieving much higher resolution imaging of nanoscale processes in real time than with optical microscopes. We have developed a vacuum sealed liquid sample electrochemical cell with electron transparent windows, microelectrodes and an electrochemical reference electrode. The system, called the EC-SEM Cell, is used to study electrochemical reactions in liquid with a standard scanning electron microscope (SEM). The central component is a microfabricated chip with a thin (50 nm) Si-rich silicon nitride (SiNx) window with lithographically defined platinum microelectrodes. We show here the design principles of the EC-SEM system, its detailed construction and how it has been used to perform a range of EC experiments, two of which are presented here. It is shown that the EC-SEM Cell can survive extended in-situ EC experiments. Before the EC experiments we characterized the beam current being deposited in the liquid as this will affect the experiments. The first EC experiment shows the influence of the electron-beam (e-beam) on a nickel solution by inducing electroless nickel deposition on the window when increasing the current density from the e-beam. The second experiment shows electrolysis in EC-SEM Cell, induced by the built-in electrodes. - Highlights: • New in-situ SEM system for electrochemistry. • In-situ Beam current measurements through liquid. • In-situ SEM E-beam-induced electroless deposition of Ni. • In-situ electrolysis
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In-situ SEM microchip setup for electrochemical experiments with water based solutions
Energy Technology Data Exchange (ETDEWEB)
Jensen, E., E-mail: eric.jensen@nanotech.dtu.dk [DTU Nanotech, Technical University of Denmark, Ørsteds Plads, Building 345E, 2800 Kongens Lyngby (Denmark); DTU CEN, Technical University of Denmark, Fysikvej, Building 307, 2800 Kongens Lyngby (Denmark); Købler, C., E-mail: carsten.kobler@nanotech.dtu.dk [DTU Nanotech, Technical University of Denmark, Ørsteds Plads, Building 345E, 2800 Kongens Lyngby (Denmark); DTU CEN, Technical University of Denmark, Fysikvej, Building 307, 2800 Kongens Lyngby (Denmark); Jensen, P.S., E-mail: psj@kemi.dtu.dk [DTU Kemi, Technical University of Denmark, Kemitorvet, Building 207, 2800 Kongens Lyngby (Denmark); Mølhave, K., E-mail: kristian.molhave@nanotech.dtu.dk [DTU Nanotech, Technical University of Denmark, Ørsteds Plads, Building 345E, 2800 Kongens Lyngby (Denmark)
2013-06-15
Studying electrochemical (EC) processes with electron microscopes offers the possibility of achieving much higher resolution imaging of nanoscale processes in real time than with optical microscopes. We have developed a vacuum sealed liquid sample electrochemical cell with electron transparent windows, microelectrodes and an electrochemical reference electrode. The system, called the EC-SEM Cell, is used to study electrochemical reactions in liquid with a standard scanning electron microscope (SEM). The central component is a microfabricated chip with a thin (50 nm) Si-rich silicon nitride (SiNx) window with lithographically defined platinum microelectrodes. We show here the design principles of the EC-SEM system, its detailed construction and how it has been used to perform a range of EC experiments, two of which are presented here. It is shown that the EC-SEM Cell can survive extended in-situ EC experiments. Before the EC experiments we characterized the beam current being deposited in the liquid as this will affect the experiments. The first EC experiment shows the influence of the electron-beam (e-beam) on a nickel solution by inducing electroless nickel deposition on the window when increasing the current density from the e-beam. The second experiment shows electrolysis in EC-SEM Cell, induced by the built-in electrodes. - Highlights: • New in-situ SEM system for electrochemistry. • In-situ Beam current measurements through liquid. • In-situ SEM E-beam-induced electroless deposition of Ni. • In-situ electrolysis.
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Directory of Open Access Journals (Sweden)
Eliane Melo Brolazo
2009-04-01
Full Text Available OBJETIVO: identificar espécies de lactobacilos isolados do conteúdo vaginal de mulheres saudáveis e assintomáticas; determinar as espécies mais prevalentes e caracterizá-las fenotipicamente. MÉTODOS: lactobacilos foram isolados em meio seletivo a partir de amostras de conteúdo vaginal de 135 mulheres, sem queixa de corrimento e com diagnóstico laboratorial negativo para infecções vaginais, acompanhadas em um ambulatório de Planejamento Familiar. Os isolados foram identificados por PCR multiplex e, quando necessário, submetidos ao sequenciamento do gene RNAr 16S. Foram também avaliados quanto à acidificação do meio de cultura, à produção de ácido láctico, de H2O2, bacteriocinas e a capacidade de adesão às células epiteliais. RESULTADOS: oitenta e três cepas de lactobacilos foram isoladas e identificadas, sendo as espécies predominantes L. crispatus (30,1%, L. jensenii (26,5%, L. gasseri (22,9% e L. vaginalis (8,4%. Apenas 20 destes isolados não produziram H2O2 em quantidades detectáveis. Das 37 linhagens selecionadas para teste de adesão a células epiteliais, 12 apresentaram adesão entre 50 a 69%, 10 apresentaram 70% ou mais, e as restantes pouca ou nenhuma adesão. Nenhum dos isolados produziu bacteriocinas. CONCLUSÕES: as espécies de lactobacilos mais prevalentes em mulheres sem vulvovaginites, isoladas em meio de cultura seletivo e identificadas por métodos moleculares, foram L. crispatus, L. jensenii e L. gasseri. Além de mais frequentes, tais linhagens também apresentaram melhor produção de H2O2 e atingiram menores valores de pH em meio de cultura.PURPOSE: to identify species of lactobacillus isolated from the vaginal contents of healthy and asymptomatic women, determining the most prevalent species and characterizing them phenotypically. METHODS: lactobacillus have been isolated in selective milieu from samples of the vaginal contents of 135 women without complaints of vaginal secretion, and with
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Afasia global sem hemiparesia: AVC ou transtorno conversivo?
Negreiros,Daniel Philippi de; Fregni,Felipe; Scalco,Andréia Zavaloni
2007-01-01
CONTEXTO: A realização de diagnóstico neurológico e psiquiátrico em ambiente de emergência hospitalar com freqüência é uma tarefa complexa e exige colaboração interdisciplinar. Um dos diagnósticos diferenciais de doenças neurológicas é o transtorno conversivo, cuja característica principal é a presença de sintomas afetando funções motoras ou sensoriais, que sugerem desordem clínica ou neurológica, porém sem doença orgânica subjacente que explique o quadro. RELATO DE CASO: Os autores relatam o...
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Improvement in the Characterization of the 2099 Al-Li Alloy by FE-SEM
Brodusch, Nicolas; Trudeau, Michel L.; Michaud, Pierre; Brochu, Mathieu; Rodrigue, Lisa; Boselli, Julien; Gauvin, Raynald
This paper describes how state-of-the-art Field-Emission Scanning Electron Microscopy (FE-SEM) can contribute to the characterization of the 2099 aluminum-lithium alloy, and metallic alloys in general. Investigations were carried out on bulk and thinned samples. BSE imaging at 3kV and STEM imaging at 30kV along with highly efficient microanalysis permitted to correlate experimental and expected structures. Although our results confirm previous studies, this work points out possible substitutions of Mg and Zn with Li, Al and Cu in the T1 precipitates. Zinc and magnesium are also present in "rice grain" shaped precipitates at the grain boundaries. The versatility of the FE-SEM is highlighted in that it can provide information at the macro and micro scales with relevant details. Its ability to probe the distribution of precipitates from nano-to micro-sizes throughout the matrix makes Field-Emission Scanning Electron Microscopy a suitable technique for the characterization of metallic alloys.
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Enhanced FIB-SEM systems for large-volume 3D imaging
Xu, C Shan; Hayworth, Kenneth J; Lu, Zhiyuan; Grob, Patricia; Hassan, Ahmed M; García-Cerdán, José G; Niyogi, Krishna K; Nogales, Eva; Weinberg, Richard J; Hess, Harald F
2017-01-01
Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) can automatically generate 3D images with superior z-axis resolution, yielding data that needs minimal image registration and related post-processing. Obstacles blocking wider adoption of FIB-SEM include slow imaging speed and lack of long-term system stability, which caps the maximum possible acquisition volume. Here, we present techniques that accelerate image acquisition while greatly improving FIB-SEM reliability, allowing the system to operate for months and generating continuously imaged volumes > 106 µm3. These volumes are large enough for connectomics, where the excellent z resolution can help in tracing of small neuronal processes and accelerate the tedious and time-consuming human proofreading effort. Even higher resolution can be achieved on smaller volumes. We present example data sets from mammalian neural tissue, Drosophila brain, and Chlamydomonas reinhardtii to illustrate the power of this novel high-resolution technique to address questions in both connectomics and cell biology. DOI: http://dx.doi.org/10.7554/eLife.25916.001 PMID:28500755
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Directory of Open Access Journals (Sweden)
Claudia Maria Bernava Aguillar
2017-01-01
Full Text Available O cenário atual do campo brasileiro faz parte do processo de inserção e intervenção das práticas impostas pelo modo de produção capitalista, capitaneadas pela classe dominante burguesa, que têm como projeto articulador, a implantação e implementação da chamnada "revolução verde", a qual revela as políticas ofensivas para dinamizar e aumentar a concentração de riquezas por meio da produção e reprodução do capital, em detrimento da luta dos trabalhadores rurais pelo acesso à terra e o cumprimento de sua função social. Para enfrentar o desafio de minimizar as ofensivas do capital, o Movimento dos Trabalhadores Rurais Sem Terra (MST criou a educação agroecologica, com o objetivo de conceber as manipulações embutidas nas contradições impostas pelo sistema, como a falta de interação das disciplinas e a fragmentação do conhecimento em virtude da falta de organicidade dos professores, a dificuldade de apropriação teórica dos alunos, a falta de investimentos para a manutenção das escolas e incentivos à pesquisa em agroecologia. As práticas educativas em Agroecologia do MST, frente às políticas neoliberais impostas pela classe dominante, se constituem no foco das reflexões iluminadas pela fundamentação teórica e a pesquisa exploratória, as quais contribuem para a análise das questões postas.
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Directory of Open Access Journals (Sweden)
Ênio Buffolo
1986-08-01
Full Text Available Os autores analisam os resultados obtidos em 391 pacientes consecutivos e não selecionados e submetidos a revascularização direta do miocárdio sem o circuito cardiopulmonar, operados de setembro de 1981 a fevereiro de 1985. Neste mesmo período, foram realizadas um total de 1568 cirurgias de revascularização, sendo esta alternativa tática aplicável em 24,9% dos casos. Da casuística apresentada, 318 (81,3% eram do sexo masculino e 73 (18,7%, do feminino e as idades de 35 a 76 anos, oscilando em torno da mediana 56. As condições pré-operatórias indicativas da cirurgia foram as seguintes: insuficiência coronária crônica 286 (73,1% casos; pós trombólise coronária 42 (10,7%; infarto agudo em evolução 18 (4,6%; pós angioplastia mal sucedida 18 (4,6%; reoperàções 14 (3,6%; síndrome intermediária 12 (3,1% e revascularização em dissecção aórtica crônica 1 caso. Pontes únicas foram realizadas em 175 (44,7% pacientes, duplas em 192 (49,1% e triplas em 24 (6,1%, com a média de 1,6 pontes/paciente. A artéria mamária foi usada para 109 casos, artéria mamária heteróloga bovina em 2, sendo, nos demais, utilizada a veia safena. A mortalidade hospitalar foi de 2,5% (10/391, o que difere, significativamente, da mortalidade de 5% verificada para um grupo de 1177 pacientes operados no mesmo período, com a circulação extracorpórea. Comparamos, prospectivamente, as complicações pós-operatórias observadas em um grupo de 378 pacientes operados sem a circulação extracorpórea, contra um grupo controle de 689 pacientes tratados da maneira convencional, no que diz respeito à incidência de arritmias, infarto per-operatório, complicações pulmonares, neurológicas, infecciosas e hemorrágicas. Verificamos uma incidência menor, estatisticamente significante, para as complicações pulmonares, neurológicas e de arritmias no grupo operado sem a circulação extracorpórea, não diferindo das demais complicações entre os
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Characterisation of nanoparticles by means of high-resolution SEM/EDS in transmission mode
International Nuclear Information System (INIS)
Hodoroaba, V-D; Rades, S; Mielke, J; Ortel, E; Salge, T; Schmidt, R
2016-01-01
Advances in scanning electron microscopy (SEM) enable the high-resolution imaging of single nanoparticles (NPs) with sizes well below 10 nm. The SEM analysis in transmission mode (T-SEM) of NPs on thin film supports has many benefits when compared to the analysis of NPs on bulk substrates. The enhanced material (mass - thickness) contrast of the T-SEM imaging mode is well suited for in-depth and, particularly valuable, to very accurate, traceable, lateral dimensional measurements of NPs. Compared to samples prepared on bulk substrates, T-SEM with energy dispersive X-ray spectroscopy (EDS) achieves a drastically improved spatial resolution of the emitted X-rays. The poor signal-to-noise ratio of the X-ray spectra emitted by a single nanoparticle (NP) can be improved by the use of high-sensitivity (high collection solid angle) silicon drift (SDD), energy-dispersive X-ray spectrometers (EDS). The EDS spectral imaging of a single NP with a spatial resolution below 10 nm has become possible. This is demonstrated by means of various examples of nanostructures. Advanced data processing of T-SEM/EDS results sets the stage for the automated classification of NPs by feature analysis. This method combines the detection of morphological structures of interest by image processing of T-SEM micrographs with the chemical classification by EDS. (paper)
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Directory of Open Access Journals (Sweden)
Antônio Francisco de Almeida Neto
Full Text Available Resumo O objetivo do estudo foi comparar o comportamento do COP e do sentido de posição articular passivo em indivíduos com e sem instabilidade de tornozelo, e correlacionar as variáveis de COP e sentido de posição articular passivo. Participaram 20 indivíduos, divididos em dois grupos: grupo estável (GE e grupo instável (GI. A avaliação do COP foi feita com o teste de apoio unipodal, com olhos abertos e fechados sobre uma plataforma de força. O teste de reposicionamento articular passivo foi realizado com os olhos vendados. O tornozelo foi posicionado em um ângulo alvo (10° e 20° e o dinamômetro movia passivamente o tornozelo, então os participantes eram instruídos a apertar o botão para parar o movimento quando sentissem que o tornozelo estava no ângulo alvo, obtendo assim o erro angular absoluto (EAA. Foram obtidas as variáveis: deslocamento total (DT; desvio padrão ântero-posterior (DPap e médio-lateral (DPml; velocidade média total (VMT; velocidade média ântero-posterior (VMap e médio-lateral (VMml. A comparação entre dados que apresentaram distribuição normal foi feita com o teste t de Student, enquanto que para DT e DPml foi utilizado o teste de Mann-Whitney. Da mesma forma, foram usados os testes de Pearson e Spearman para correlacionar as variáveis. Foi adotado α < 0,05. Houve diferença entre EAA-10° (p < 0,05. Foram encontradas fortes correlações entre: EAA-10° e VMT (p < 0,01 r = −0,867; EAA-10° e VMap (p < 0,01 r = −0,854; EAA-10° e VMml (p < 0,01 r = −0,771, na condição olhos abertos, e EAA-10° e DT (p < 0,05 r = −0,666; EAA-10° e DPap (p < 0,05 r = −0,685 e EAA-10° e VMml (p < 0,05 r = −0,766 na condição olhos fechados. Entorses de tornozelo prejudicam o sentido de posição, sem afetar o equilíbrio.
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Rodgers, Michelle; Zimar, Heather
2004-01-01
The "SEM Anthology" is a compilation of articles by more than 30 enrollment management professionals from a variety of institutions across the country. This collection, which has appeared in SEM Monthly over the past year, chronicles Strategic Enrollment Management efforts at campuses nationwide. The book illustrates the successes and challenges…
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O epitélio respiratório em ratos Wistar
Directory of Open Access Journals (Sweden)
Nuno A.A. Castelo Branco
2003-09-01
animals were sacrificed at 3.5 months of age, and respiratory epithelial fragments were excised and prepared for scanning (SEM and transmission (TEM electron microscopy. Brush cells (BC were frequently observed with TEM, but with SEM they were often covered by the cilia of neighbouring cells. BC were always observed at the center of a ring of secretory cells (SC, in a rosetta-shaped formation. In TEM, the microvilli of SC surrounding the BC were uniform, and had the same density and shape in all cells. Multivesicular bodies were identified in areas within the BC. Formation and budding of vesicles from ciliary plasma membranes and from BC microvilli were frequently observed in both TEM and SEM. These data contribute to the understanding of the BC function.REV PORT PNEUMOL 2003; IX (5: 381-388 Palavras-chave: ruÃdo de baixa frequência, célula em escova, célula secretora, cÃlios, microvilosidade, morfologia, microscopia electrónica, Keywords: low frequency noise, brush cell, secretory cell, cilia, microvilli, morphology, electron microscopy
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SEM and Raman studies of CNT films on porous Si
Belka, R.; Keczkowska, J.; Suchańska, M.; Firek, P.; Wronka, H.; Kozłowski, M.; Radomska, J.; Czerwosz, E.; Craciunoiu, F.
2017-08-01
Carbon nanotube (CNT) films deposited on different porous silica substrates were studied by Scanning Electron Microscopy (SEM) and Raman Spectroscopy (RS). The films samples were prepared by a two-step method consisting of PVD and CVD processes. In the first step the nanocomposite Ni-C film was obtained by evaporation in dynamic vacuum from two separated sources of fullerenes and nickel acetate. Those films were deposited on porous silica and DLC/porous silica substrates. Analysis of SEM imaging showed that the obtained film are composed of carbon nanotubes, the distribution, size and quality of which depend on the type of substrate. The CNT films were studied by RS method to determine the influence of the substrate type on disordering of carbonaceous structure and quality of CNT in deposited films.
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Directory of Open Access Journals (Sweden)
Syed Shahid Habib
2011-01-01
Full Text Available FUNDAMENTO: Há grande interesse no uso de proteína C-reativa de alta sensibilidade (PCR-as para avaliação de risco. Altos níveis de PCR-as no início da síndrome coronária aguda (SCA, antes da necrose tecidual, pode ser um marcador substituto para comorbidades cardiovasculares. OBJETIVO: Dessa forma, nosso objetivo foi estudar diferentes medidas de seguimento de níveis de PCR-as em pacientes com SCA e comparar as diferenças entre infarto do miocárdio sem elevação do segmento ST (NSTEMI com pacientes apresentando elevação do segmento ST (STEMI. MÉTODOS: Este é um estudo observacional. Dos 89 pacientes recrutados, 60 apresentavam infarto agudo do miocárdio (IAM. Três níveis seriados de PCR-us, a nível basal na hospitalização antes de 12 horas após inicio dos sintomas, níveis de pico 36-48 horas após hospitalização e níveis de acompanhamento após 4 a 6 semanas foram analisados e comparados entre pacientes com (IAMCSST e sem supradesnivelamento do segmento ST (IAMSSST. RESULTADOS: Pacientes com IAMCSST tinham IMC significantemente mais alta quando comparados com pacientes IAMSSST. Os níveis de creatino quinase fração MB (CK-MB e aspartato aminotransferase (AST eram significantemente mais altos em pacientes com IAMCSST quando comparados com pacientes com IAMSSST (p<0,05. Os níveis de PCR a nível basal e no acompanhamento não diferiram de forma significante entre os dois grupos (p=0,2152 e p=0,4686 respectivamente. Houve uma diferença significante nos níveis de pico de PCR entre os dois grupos. No grupo de pacientes com IAMCSST os níveis foram significantemente mais altos quando comparados aos pacientes com IAMSSST (p=0,0464. CONCLUSÃO: Pacientes com IAMCSST apresentam picos significantemente mais elevados de PCR quando comparados a pacientes IAMSSST. Esses dados sugerem que o processo inflamatório tem um papel independente na patogênese do infarto do miocárdio. Dessa forma, os níveis de PCR podem ajudar na
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Precise and economic FIB/SEM for CLEM: with 2 nm voxels through mitosis.
Luckner, Manja; Wanner, Gerhard
2018-05-23
A portfolio is presented documenting economic, high-resolution correlative focused ion beam scanning electron microscopy (FIB/SEM) in routine, comprising: (i) the use of custom-labeled slides and coverslips, (ii) embedding of cells in thin, or ultra-thin resin layers for correlative light and electron microscopy (CLEM) and (iii) the claim to reach the highest resolution possible with FIB/SEM in xyz. Regions of interest (ROIs) defined in light microscope (LM), can be relocated quickly and precisely in SEM. As proof of principle, HeLa cells were investigated in 3D context at all stages of the cell cycle, documenting ultrastructural changes during mitosis: nuclear envelope breakdown and reassembly, Golgi degradation and reconstitution and the formation of the midzone and midbody.
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Directory of Open Access Journals (Sweden)
Leny N. M. Passos
2005-03-01
Full Text Available Uma doaç��o de aproximadamente 475mL de sangue depleta em média 242 ± 17 mg de ferro do doador, o que pode ter conseqüências variáveis em suas reservas e na sua saúde. Tivemos por objetivo avaliar se doadores de sangue do Hemocentro do Amazonas - Hemoam desenvolvem sideropenia sem anemia após doações consecutivas. A ferritina sérica foi medida em 528 doadores de sangue, do sexo masculino, com idade entre 18 a 61 anos, divididos em 313 doadores de repetição, com 4 ou mais doações regulares, e 215 primodoadores, que compareceram ao Hemocentro do Amazonas no período de setembro de 2001 a junho de 2002. Depleção do depósito de ferro, definida por níveis de ferritina menores de 20 ng/L, foi encontrada em 7,4% [16/215] dos primodoadores e em 48,6% [152/313] dos doadores de repetição. Utilizando-se de um critério mais rigoroso, como valores de ferritina A blood donation of 475 mL could deplete 242 ± 17 mg of iron from blood donors. The objective of this report is to evaluate if blood donors could develop sideropenia without anemia after several donations. Serum levels of ferritin were measured in 528 male blood donors, with ages ranging from 18 to 61 years old. A total of 313 of them had made 4 or more donations and 215 of them were first time donors. They donated blood in the Hemocentro do Amazonas - Hemoam, from September 2001 to June 2002. Deletion of iron stores characterized by serum ferritin levels of less than 20 ng/L was found in 7.4% (16/215 of first time donors, and in 48.6% (152/313 of multiple donors. With more stringent criteria of ferritin values less than 12 ng/L, 3.7% (8/215 of first-time donors as opposed to 24.9% (78/313 of multiple donors showed severe depletions. We concluded that multiple donors, after more than 5 repeated donations, are at risk of depleted iron and ferritin levels. It is important to implant protocols of iron supplementation for these donors to avoid damage to their health and
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Nutrientes no mantilho em pastagem nativa sob distintos manejos
Directory of Open Access Journals (Sweden)
Heringer Ingrid
2002-01-01
Full Text Available A avaliação da quantidade de nutrientes no mantilho é importante para verificar a ciclagem de nutrientes e a preservação da fertilidade do solo. O teor e a quantidade de nutrientes no mantilho e material senescente foram estudados em pastagem nativa sob pastejo, sujeita à queima e manejos alternativos, durante um ano, nos Campos de Cima da Serra, no Rio Grande do Sul. O acúmulo de mantilho foi coletado em gaiolas de exclusão ao pastejo, a cada 90 dias. O mantilho representou o material morto desprendido da planta existente junto à superfície do solo. A esta fração foi adicionado o material senescente ligado à planta. Os tratamentos foram pastagem nativa sob pastejo sem queima e sem roçada há 32 anos, melhorada há sete anos e com queima bienal há mais de 100 anos. O delineamento experimental foi completamente casualizado com três repetições. Os teores de Ca e Mg no mantilho mais material senescente foram inferiores no tratamento queimado em relação às áreas sem queima. O melhoramento da pastagem aumentou os teores de nutrientes nos tecidos. A quantidade acumulada de nutrientes, reflexo da produção de mantilho e material senescente, foi maior nos sistemas sem queima.
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Scanning electron microscopy and micro-analyses
International Nuclear Information System (INIS)
Brisset, F.; Repoux, L.; Ruste, J.; Grillon, F.; Robaut, F.
2008-01-01
Scanning electron microscopy (SEM) and the related micro-analyses are involved in extremely various domains, from the academic environments to the industrial ones. The overall theoretical bases, the main technical characteristics, and some complements of information about practical usage and maintenance are developed in this book. high-vacuum and controlled-vacuum electron microscopes are thoroughly presented, as well as the last generation of EDS (energy dispersive spectrometer) and WDS (wavelength dispersive spectrometer) micro-analysers. Beside these main topics, other analysis or observation techniques are approached, such as EBSD (electron backscattering diffraction), 3-D imaging, FIB (focussed ion beams), Monte-Carlo simulations, in-situ tests etc.. This book, in French language, is the only one which treats of this subject in such an exhaustive way. It represents the actualized and totally updated version of a previous edition of 1979. It gathers the lectures given in 2006 at the summer school of Saint Martin d'Heres (France). Content: 1 - electron-matter interactions; 2 - characteristic X-radiation, Bremsstrahlung; 3 - electron guns in SEM; 4 - elements of electronic optics; 5 - vacuum techniques; 6 - detectors used in SEM; 7 - image formation and optimization in SEM; 7a - SEM practical instructions for use; 8 - controlled pressure microscopy; 8a - applications; 9 - energy selection X-spectrometers (energy dispersive spectrometers - EDS); 9a - EDS analysis; 9b - X-EDS mapping; 10 - technological aspects of WDS; 11 - processing of EDS and WDS spectra; 12 - X-microanalysis quantifying methods; 12a - quantitative WDS microanalysis of very light elements; 13 - statistics: precision and detection limits in microanalysis; 14 - analysis of stratified samples; 15 - crystallography applied to EBSD; 16 - EBSD: history, principle and applications; 16a - EBSD analysis; 17 - Monte Carlo simulation; 18 - insulating samples in SEM and X-ray microanalysis; 18a - insulating
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Helium leak testing of scanning electron microscope
International Nuclear Information System (INIS)
Ahmad, Anis; Tripathi, S.K.; Mukherjee, D.
2015-01-01
Scanning Electron Microscope (SEM) is a specialized electron-optical device which is used for imaging of miniscule features on topography of material specimens. Conventional SEMs used finely focused high energy (about 30 KeV) electron beam probes of diameter of about 10nm for imaging of solid conducting specimens. Vacuum of the order of 10"-"5 Torr is prerequisite for conventional Tungsten filament type SEMs. One such SEM was received from one of our laboratory in BARC with a major leak owing to persisting poor vacuum condition despite continuous pumping for several hours. He-Leak Detection of the SEM was carried out at AFD using vacuum spray Technique and various potential leak joints numbering more than fifty were helium leak tested. The major leak was detected in the TMP damper bellow. The part was later replaced and the repeat helium leak testing of the system was carried out using vacuum spray technique. The vacuum in SEM is achieved is better than 10"-"5 torr and system is now working satisfactorily. (author)
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Refinement of Monte Carlo simulations of electron-specimen interaction in low-voltage SEM
International Nuclear Information System (INIS)
Kieft, Erik; Bosch, Eric
2008-01-01
A Monte Carlo tool is presented for the simulation of secondary electron (SE) emission in a scanning electron microscope (SEM). The tool is based on the Geant4 platform of CERN. The modularity of this platform makes it comparatively easy to add and test individual physical models. Our aim has been to develop a flexible and generally applicable tool, while at the same time including a good description of low-energy (<50 eV) interactions of electrons with matter. To this end we have combined Mott cross-sections with phonon-scattering based cross-sections for the elastic scattering of electrons, and we have adopted a dielectric function theory approach for inelastic scattering and generation of SEs. A detailed model of the electromagnetic fields from an actual SEM column has been included in the tool for ray tracing of secondary and backscattered electrons. Our models have been validated against experimental results through comparison of the simulation results with experimental yields, SE spectra and SEM images. It is demonstrated that the resulting simulation package is capable of quantitatively predicting experimental SEM images and is an important tool in building a deeper understanding of SEM imaging.
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Redução de fósforo em dietas para frangos com base em valores de equivalência da fitase
Directory of Open Access Journals (Sweden)
Luciana de Paula Naves
2014-01-01
Full Text Available O objetivo deste trabalho foi avaliar o uso de valores de equivalência da fitase como base para redução de fósforo disponível (P-disp em dietas para frangos. Foram avaliados dez planos nutricionais com seis repetições de 15 aves cada uma. Avaliaram-se: desempenho, teor de cinzas na tíbia e custo da ração. De 1 a 7 e de 36 a 42 dias de idade, as aves receberam dieta basal; de 8 a 21 dias, dieta sem fitase contendo 3,9 g kg-1 de P-disp e quatro dietas com fitase contendo de 1,1 a 2,5 g kg-1 de P-disp; e de 22 a 35 dias, dieta sem fitase contendo 3,4 g kg-1 de P-disp mais dieta com fitase contendo 1,6 g kg-1 de P-disp. O melhor plano nutricional foi composto pelas dietas: 4,7 g kg-1 de P-disp sem fitase (1 a 7 dias; 2,0 g kg-1 de P-disp suplementada com fitase (8 a 21 dias; 3,4 g kg-1 de P-disp em ração sem fitase (22 a 35 dias; e 3,0 g kg-1 de P-disp em ração sem fitase (36 a 42 dias. A redução do P-disp ocorre no período de 8 a 21 dias de idade e corresponde a 2,0 g kg-1 de ração suplementada com fitase.
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Energy Technology Data Exchange (ETDEWEB)
Dhillon, Shweta; Kant, Rama, E-mail: rkant@chemistry.du.ac.in
2013-10-01
Area measurements from cyclic voltammetry (CV) and image from scanning electron microscopy (SEM) are used to characterize electrode statistical morphology, 3D surface reconstruction and its electroactivity. SEM images of single phased materials correspond to two-dimensional (2D) projections of 3D structures, leading to an incomplete characterization. Lack of third dimension information in SEM image is circumvented using equivalence between denoised SEM image and CV area measurements. This CV-SEM method can be used to estimate power spectral density (PSD), width, gradient, finite fractal nature of roughness and local morphology of the electrode. We show that the surface morphological statistical property like distribution function of gradient can be related to local electro-activity. Electrode surface gradient micrographs generated here can provide map of electro-activity sites. Finally, the densely and uniformly packed small gradient over the Pt-surface is the determining criterion for high intrinsic electrode activity.
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International Nuclear Information System (INIS)
Dhillon, Shweta; Kant, Rama
2013-01-01
Area measurements from cyclic voltammetry (CV) and image from scanning electron microscopy (SEM) are used to characterize electrode statistical morphology, 3D surface reconstruction and its electroactivity. SEM images of single phased materials correspond to two-dimensional (2D) projections of 3D structures, leading to an incomplete characterization. Lack of third dimension information in SEM image is circumvented using equivalence between denoised SEM image and CV area measurements. This CV-SEM method can be used to estimate power spectral density (PSD), width, gradient, finite fractal nature of roughness and local morphology of the electrode. We show that the surface morphological statistical property like distribution function of gradient can be related to local electro-activity. Electrode surface gradient micrographs generated here can provide map of electro-activity sites. Finally, the densely and uniformly packed small gradient over the Pt-surface is the determining criterion for high intrinsic electrode activity.
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Full surface examination of small spheres with a computer controlled scanning electron microscope
International Nuclear Information System (INIS)
Ward, C.M.; Willenborg, D.L.; Montgomery, K.L.
1979-01-01
This report discusses a computer automated stage and Scanning Electron Microscopy (SEM) system for detecting defects in glass spheres for inertial confinement laser fusion experiments. This system detects submicron defects and permits inclusion of acceptable spheres in targets after examination. The stage used to examine and manipulate the spheres through 4π steradians is described. Primary image recording is made on a roster scanning video disc. The need for SEM stability and methods of achieving it are discussed
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International Nuclear Information System (INIS)
Sato, Mitsugu; Ishitani, Tohru; Watanabe, Shunya; Nakagawa, Mine
2004-01-01
The depth of field (DoF) in scanning electron microscope (SEM) images has been determined by estimating the change of image sharpness or resolution near the exact focus position. The image sharpness or resolution along the optical axis is determined by calculating the information-passing capacity (IPC) of an optical system taking into account the effect of pixel size of the image. The change of image sharpness near the exact focus position is determined by measuring the slope gradient of the line profile in SEM images obtained at various focal positions of beam. The change of image sharpness along the optical axis determined by the IPC agrees well with those determined by the slope gradient of line profiles in SEM images when a Gaussian distribution having radius 0.86L p (L p : pixel size in image) at which the intensity has fallen to 1/e of the maximum is applied to the IPC calculation for each pixel intensity. The change of image sharpness near the exact focus position has also been compared with those determined by the CG (Contrast-to-Gradient) method. The CG method slightly underestimates the change of image sharpness compared with those determined by the IPC method
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SEM-analysis of grain boundary porosity in three S-176 specimens
International Nuclear Information System (INIS)
Malen, K.; Birath, S.; Mattsson, O.
1980-10-01
Porosity in UO 2 -fuel has been studied in scanning electron microscope (SEM). The aim was to obtain a basis for evaluation of porosity in high burnup power reactor fuel. Three specimens have been analyzed. In the high temperature zones porosity can be seen both on grain boundaries and at grain edges. In the low temperature regions very little changes seem to have occurred during irradiation. (author)
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Directory of Open Access Journals (Sweden)
Ana Paula Klautau Leite
2008-10-01
Full Text Available OBJETIVO: Determinar o valor agregado da fase sem meio de contraste da tomografia computadorizada do abdome em pacientes sem diagnóstico determinado ou em estadiamento tumoral. MATERIAIS E MÉTODOS: Estudo prospectivo e transversal em 100 pacientes consecutivos submetidos a tomografia computadorizada abdominal sem e com meio de contraste intravenoso. Dois examinadores avaliaram todos os exames, procurando estabelecer, através da fase com meio de contraste intravenoso (primeira análise e posteriormente através da fase sem contraste (segunda análise, o diagnóstico principal e os secundários em função da indicação clínica do exame. Mediu-se a freqüência de mudança diagnóstica decorrente da análise combinada das fases pré- e pós-contraste intravenoso. Casos que tiveram mudança diagnóstica foram avaliados por especialistas clínicos para determinar se implicaria mudanças de conduta. RESULTADOS: Diagnósticos principal e secundário foram modificados em 1 e 18 casos, respectivamente (p = 1,000; p = 0,143. Os diagnósticos modificados foram: esteatose, definição de nódulo em adrenal, nefrolitíase, classificação de cistos renais e calcificação hepática. Nos casos em que a fase sem contraste modificou o diagnóstico, os especialistas mudaram sua conduta em 14/19 (73% dos pacientes (p = 0,038. CONCLUSÃO: A fase sem contraste não modificou significativamente o diagnóstico principal ou secundário. Porém, as mudanças nos diagnósticos secundários influenciaram na conduta adotada pelos especialistas.OBJECTIVE: To determine the role of the unenhanced phase of abdominal computed tomography in patients without a definite diagnosis or undergoing tumor staging. MATERIALS AND METHODS: A prospective and transversal study was developed with 100 consecutive patients submitted to unenhanced and contrast-enhanced abdominal computed tomography. Two observers evaluated all the computed tomography images in the contrast-enhanced phase
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Infarto do miocárdio em atleta jovem associado ao uso de suplemento dietético rico em efedrina
Forte,Rafael Yared; Precoma-Neto,Daniel; Chiminacio Neto,Nelson; Maia,Francisco; Faria-Neto,José Rocha
2006-01-01
Suplementos dietéticos que contêm efedrina e outros alcalóides relacionados à efedrina são largamente consumidos em vários países, com propósito de estímulo energético e perda de peso. Mesmo sendo proibida a sua comercialização no Brasil, esses produtos podem ser comprados ilegalmente pela Internet ou em academias. Relatamos a seguir o caso de um jovem atleta, sem fatores de risco para doença cardiovascular, que apresentou infarto do miocárdio no período em que fez uso de suplemento rico em e...
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Potential Applications of Scanning Probe Microscopy in Forensic Science
International Nuclear Information System (INIS)
Watson, G S; Watson, J A
2007-01-01
The forensic community utilises a myriad of techniques to investigate a wide range of materials, from paint flakes to DNA. The various microscopic techniques have provided some of the greatest contributions, e.g., FT-IR (Fourier-transform infrared) microspectroscopy utilised in copy toner discrimination, multi-layer automobile paint fragment examination, etc, SEM-EDA (scanning electron microscopy with energy dispersive analysis) used to investigate glass fragments, fibers, and explosives, and SEM in microsampling for elemental analysis, just to name a few. This study demonstrates the ability of the Scanning Probe Microscope (SPM) to analyse human fingerprints on surfaces utilising a step-and-scan feature, enabling analysis of a larger field-of-view. We also extend a line crossings study by incorporating height analysis and surface roughness measurements. The study demonstrates the potential for SPM techniques to be utilised for forensic analysis which could complement the more traditional methodologies used in such investigations
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Potential Applications of Scanning Probe Microscopy in Forensic Science
Energy Technology Data Exchange (ETDEWEB)
Watson, G S [Nanoscale Science and Technology Centre, School of Science, Griffith University, Kessels Rd, Nathan, QLD, 4111 (Australia); Watson, J A [Nanoscale Science and Technology Centre, School of Science, Griffith University, Kessels Rd, Nathan, QLD, 4111 (Australia)
2007-04-15
The forensic community utilises a myriad of techniques to investigate a wide range of materials, from paint flakes to DNA. The various microscopic techniques have provided some of the greatest contributions, e.g., FT-IR (Fourier-transform infrared) microspectroscopy utilised in copy toner discrimination, multi-layer automobile paint fragment examination, etc, SEM-EDA (scanning electron microscopy with energy dispersive analysis) used to investigate glass fragments, fibers, and explosives, and SEM in microsampling for elemental analysis, just to name a few. This study demonstrates the ability of the Scanning Probe Microscope (SPM) to analyse human fingerprints on surfaces utilising a step-and-scan feature, enabling analysis of a larger field-of-view. We also extend a line crossings study by incorporating height analysis and surface roughness measurements. The study demonstrates the potential for SPM techniques to be utilised for forensic analysis which could complement the more traditional methodologies used in such investigations.
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Simulation and Characterization of a Miniaturized Scanning Electron Microscope
Gaskin, Jessica A.; Jerman, Gregory A.; Medley, Stephanie; Gregory, Don; Abbott, Terry O.; Sampson, Allen R.
2011-01-01
A miniaturized Scanning Electron Microscope (mSEM) for in-situ lunar investigations is being developed at NASA Marshall Space Flight Center with colleagues from the University of Alabama in Huntsville (UAH), Advanced Research Systems (ARS), the University of Tennessee in Knoxville (UTK) and Case Western Reserve University (CWRU). This effort focuses on the characterization of individual components of the mSEM and simulation of the complete system. SEMs can provide information on the size, shape, morphology and chemical composition of lunar regolith. Understanding these basic properties will allow us to better estimate the challenges associated with In-Situ Resource Utilization and to improve our basic science knowledge of the lunar surface (either precluding the need for sample return or allowing differentiation of unique samples to be returned to Earth.) The main components of the mSEM prototype includes: a cold field emission electron gun (CFEG), focusing lens, deflection/scanning system and backscatter electron detector. Of these, the electron gun development is of particular importance as it dictates much of the design of the remaining components. A CFEG was chosen for use with the lunar mSEM as its emission does not depend on heating of the tungsten emitter (lower power), it offers a long operation lifetime, is orders of magnitude brighter than tungsten hairpin guns, has a small source size and exhibits low beam energy spread.
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Cryo-SEM studies of latex/ceramic nanoparticle coating microstructure development.
Luo, Hui; Scriven, L E; Francis, Lorraine F
2007-12-15
Cryogenic scanning electron microscopy (cryo-SEM) was used to investigate microstructure development of composite coatings prepared from dispersions of antimony-doped tin oxide (ATO) nanoparticles (approximately 30 nm) or indium tin oxide (ITO) nanoparticles (approximately 40 nm) and latex particles (polydisperse, D(v): approximately 300 nm). Cryo-SEM images of ATO/latex dispersions as-frozen show small clusters of ATO and individual latex particles homogeneously distribute in a frozen water matrix. In contrast, cryo-SEM images of ITO/latex dispersions as-frozen show ITO particles adsorb onto latex particle surfaces. Electrostatic repulsion between negatively charged ATO and negatively charged latex particles stabilizes the ATO/latex dispersion, whereas in ITO/latex dispersion, positively charged ITO particles are attracted onto surfaces of negatively charged latex particles. These results are consistent with calculations of interaction potentials from past research. Cryo-SEM images of frozen and fractured coatings reveal that both ceramic nanoparticles and latex become more concentrated as drying proceeds; larger latex particles consolidate with ceramic nanoparticles in the interstitial spaces. With more drying, compaction flattens the latex-latex particle contacts and shrinks the voids between them. Thus, ceramic nanoparticles are forced to pack closely in the interstitial spaces, forming an interconnected network. Finally, latex particles partially coalesce at their flattened contacts, thereby yielding a coherent coating. The research reveals how nanoparticles segregate and interconnect among latex particles during drying.
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Directory of Open Access Journals (Sweden)
Ana Guiomar Matos Santiago Reis
2010-08-01
Full Text Available Twenty Thoroughbred racehorses were ultrasonographically evaluated to determine the relation between normal values of the cross-sectional area (CSA of the right and left forelimbs superficial digital flexor tendons (SDFT in the metacarpal region for trained and untrained Thoroughbreds racehorses. Ultrasonography revealed that CSA at 26cm distal to the accessory carpal bone is larger than other proximal levels, for either left or right forelimbs. In addition, the CSA at 2, 4, 6, 8, 10, 12 and 14cm distal to the accessory carpal bone of the left forelimb are larger (P0.05 between left and right forelimb for CSA of the SDFT, at any level, for either trained or untrained horses, and there was no significant difference between untrained or trained horses for the CSA of right forelimb. In conclusion, the CSA of the left forelimb SDFT for horses that had been in continuous race training remains larger when they were trained anticlockwise, contrary to horses that had not been training for more than one year.Vinte cavalos da raça Puro Sangue Inglês de corrida foram submetidos a exame ultrassonográfico, com o intuito de determinar a relação entre os valores normais da área do tendão flexor digital superficial (TFDS na região metacarpiana dos membros torácicos direito e esquerdo, em cavalos com e sem treinamento. O exame ultrassonográfico revelou que a área do tendão 26cm distal ao osso acessório do carpo é maior em comparação com as alturas proximais, tanto nos membros torácicos esquerdos, como nos membros torácicos direitos. Além disso, a área do TFDS nas alturas 2, 4, 6, 8, 10, 12 e 14cm, no membro torácico esquerdo, é maior (P0,05 nas áreas do TFDS entre os membros torácicos direito e esquerdo, tanto para os animais em treinamento, como para os animais sem treinamento. Também não foi encontrada diferença significativa em comparação com o membro direito dos cavalos em treinamento e sem treinamento. Conclui-se que os cavalos
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Directory of Open Access Journals (Sweden)
Takahiro eSonomura
2013-02-01
Full Text Available Three-dimensional reconstruction of ultrastructure of rat brain with minimal effort has recently been realized by scanning electron microscopy combined with focused ion beam milling (FIB-SEM. Because application of immunohistochemical staining to electron microscopy has a great advantage in that molecules of interest are specifically localized in ultrastructures, we here tried to apply immunocytochemistry to FIB-SEM and correlate immunoreactivity in confocal laser-scanning microcopy (CF-LSM with that in FIB-SEM. The dendrites of medium-sized spiny neurons in rat neostriatum were visualized with a recombinant viral vector, which labeled the infected neurons with membrane-targeted GFP in a Golgi stain-like fashion, and thalamostriatal afferent terminals were immunolabeled with Cy5 fluorescence for vesicular glutamate transporter 2 (VGluT2. After detecting the sites of terminals apposed to the dendrites in CF-LSM, GFP and VGluT2 immunoreactivities were further developed for electron microscopy by the immunogold/silver enhancement and immunoperoxidase/diaminobenzidine (DAB methods, respectively. In the contrast-inverted FIB-SEM images, silver precipitation and DAB deposits were observed as fine dark grains and diffuse dense profiles, respectively, indicating that these immunoreactivities were easily recognizable as in the images of transmission electron microscopy. In the sites of interest, some appositions were revealed to display synaptic specialization of asymmetric type. The present method is thus useful in the three-dimensional analysis of immunocytochemically differentiated synaptic connection in the central neural circuit.
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O arquivo e o sonho: a montagem como processo de mediação em “Sem Sol”, de Chris Marker
Directory of Open Access Journals (Sweden)
Julia Gonçalves Declie Fagioli
2015-07-01
Full Text Available O que propomos, no presente artigo, é pensar a montagem – e, mais especificamente, a montagem de imagens de arquivo – como processo de mediação entre as imagens e o espectador. Para isso, recorremos às ideias de Georges Didi-Huberman para refletir sobre as imagens do sonho e as imagens de arquivo. Ambas – cada uma à sua maneira – carregam vestígios da memória e possuem caráter lacunar. Apenas quando são articuladas no sonho, ou na montagem – no caso do cinema documentário – que se configura um novo sentido. Analisaremos “Sem sol” de Chris Marker, em que as imagens de arquivo são montadas de forma a proporcionar uma reflexão sobre a memória e a história. O filme é construído com imagens de arquivo e leituras de cartas de um cinegrafista viajante, o que confere à narrativa um caráter imaginativo, característica essencial da lembrança e da memória.
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Fractionation of Pb in Soil of Abandoned Pb Mine by SEM-EDX and ...
African Journals Online (AJOL)
Therefore, scanning electron microscopy coupled with energy dispersive X-ray spectrometer (SEM-EDX) were used for the identification of fractional forms of Pb that are liable to leach out/down from the soil matrix of the abandoned mine site to surface-andunderground water bodies of the nearby localities, and to determine ...
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La complejidad de la opción en español: una perspectiva semántica-pragmática
Directory of Open Access Journals (Sweden)
Daniel Mazzaro
2011-10-01
Full Text Available Resumo: Este trabalho apresenta uma análise das construções opositivas (ou contra-argumentativas em espanhol à luz de algumas teorias semântico-pragmáticas. Estas construções, complexas devido à não-linearidade de sua estrutura e à exigência de compreensão por parte do ouvinte/leitor, não são, entre si, sinônimas. Os conectores usados em tais construções não são sempre, apesar da idéia que transmitem, intercambiáveis.Palavras-chave: ensino de língua estrangeira; língua espanhola; semântica; pragmática; conjunção.Resumen: Este trabajo presenta un análisis de las construcciones opositivas (o contraargumentativas en español a la luz de las aportaciones semántico-pragmáticas. Estas construcciones, complejas debido a la no-linealidad de su estructura y a la exigencia de comprensión por parte del oyente/lector, no son, entre sí, sinónimas. Los conectores usados en tales construcciones no son siempre, pese a la idea que transmiten, intercambiables.Palabras-clave: Enseñanza de lengua extranjera; lengua española; semántica; pragmática; conector.Keywords: Foreign language teaching; Spanish; semantics; pragmatics; conectives.
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Scanning electronic microscopy on clays in soils used as road foundations
International Nuclear Information System (INIS)
Barelli, N.
1982-01-01
The scanning electron microscope (SEM) proves to be ideally suited for studying the morphology, texture and fabric of clays in soils used as road foundation. It is also seen that certain samples are easier to examine by SEM because of their larger crystallite sizes, better crystallinities and open textures. (C.L.B.) [pt
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Combination of FTIR and SEM for Identifying Freshwater-Cultured Pearls from Different Quality
Satitkune, Somruedee; Monarumit, Natthapong; Boonmee, Chakkrich; Phlayrahan, Aumaparn; Promdee, Kittiphop; Won-in, Krit
2016-03-01
The freshwater-cultured pearl ( Chamberlainia hainesiana species) is an organic gemstone mainly composed of calcium carbonate mineral including calcite, aragonite and vaterite phases. Generally, the quality of freshwater-cultured pearl is based on its luster. The high luster pearl is full of the aragonite phase without vaterite phase. On the other hand, the low luster pearl consists of aragonite and vaterite phases. These data could be proved by the Fourier Transform Infrared (FTIR) spectroscopy combined with the scanning electron microscopy (SEM). As the results, the high luster pearl similarly shows the FTIR spectrum of aragonite phase, and also, it shows the hexagonal shape of aragonite for the SEM image. On the other hand, the FTIR spectrum of low luster pearl has been pointed to the mixture component among aragonite and vaterite phases, and based on the SEM image; the irregular form is also interpreted to the mixture of aragonite and vaterite phases. This research concludes that the quality of freshwater-cultured pearls can be identified by the combination data of FTIR spectra and SEM images. These techniques are suitable for applied gemology.
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SD-SEM: sparse-dense correspondence for 3D reconstruction of microscopic samples.
Baghaie, Ahmadreza; Tafti, Ahmad P; Owen, Heather A; D'Souza, Roshan M; Yu, Zeyun
2017-06-01
Scanning electron microscopy (SEM) imaging has been a principal component of many studies in biomedical, mechanical, and materials sciences since its emergence. Despite the high resolution of captured images, they remain two-dimensional (2D). In this work, a novel framework using sparse-dense correspondence is introduced and investigated for 3D reconstruction of stereo SEM images. SEM micrographs from microscopic samples are captured by tilting the specimen stage by a known angle. The pair of SEM micrographs is then rectified using sparse scale invariant feature transform (SIFT) features/descriptors and a contrario RANSAC for matching outlier removal to ensure a gross horizontal displacement between corresponding points. This is followed by dense correspondence estimation using dense SIFT descriptors and employing a factor graph representation of the energy minimization functional and loopy belief propagation (LBP) as means of optimization. Given the pixel-by-pixel correspondence and the tilt angle of the specimen stage during the acquisition of micrographs, depth can be recovered. Extensive tests reveal the strength of the proposed method for high-quality reconstruction of microscopic samples. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Directory of Open Access Journals (Sweden)
José C. Fraga
2001-10-01
Full Text Available OBJETIVOS: descrever as indicações e resultados da supraglotoplastia endoscópica em crianças com e sem lesão neurológica que apresentavam laringomalacia grave. MÉTODOS: estudo retrospectivo de 8 crianças com laringomalacia grave submetidas à supraglotoplastia endoscópica com material de microcirurgia. Quatro crianças tinham paralisia cerebral (todas masculinas, idade média 6 anos e 4 eram crianças sem doença neurológica (3 femininas, idade média de 11,5 meses. As indicações da cirurgia foram dificuldade respiratória em repouso e/ou esforço, dificuldade de deglutição, deficiência de crescimento e baixa saturação transcutânea de oxigênio. Estudo polissonográfico realizado nas últimas duas crianças mostrou dessaturação na oximetria, apnéia e hipoventilação durante o sono. As crianças receberam corticóide e antibiótico no pré-operatório. RESULTADOS: todas as crianças sem doença neurológica apresentaram melhora significativa do estridor e da obstrução ventilatória. Das crianças com paralisia cerebral, uma necessitou traqueostomia logo após a cirurgia por edema e tecido de granulação supraglótico. As outras três apresentaram melhora clínica inicial, mas pioraram progressivamente, apesar da realização de outros procedimentos: uma necessitou nova supraglotoplastia após 6 meses; outra necessitou traqueostomia após 7 meses. Aquelas sem traqueostomia persistem com obstrução ventilatória grave. Não foi observada complicação do procedimento cirúrgico. CONCLUSÕES: 1 a supraglotoplastia é bem tolerada e sem complicações na criança; 2 a supraglotoplastia, neste estudo, mostrou-se eficaz no tratamento da laringomalacia grave em crianças sem paralisia cerebral; entretanto, a supraglotoplastia não melhorou a obstrução ventilatória de crianças com paralisia cerebral e laringomalacia grave.OBJECTIVE: to describe indications and results of supraglottoplasty for severe laryngomalacia in
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Minimal resin embedding of multicellular specimens for targeted FIB-SEM imaging.
Schieber, Nicole L; Machado, Pedro; Markert, Sebastian M; Stigloher, Christian; Schwab, Yannick; Steyer, Anna M
2017-01-01
Correlative light and electron microscopy (CLEM) is a powerful tool to perform ultrastructural analysis of targeted tissues or cells. The large field of view of the light microscope (LM) enables quick and efficient surveys of the whole specimen. It is also compatible with live imaging, giving access to functional assays. CLEM protocols take advantage of the features to efficiently retrace the position of targeted sites when switching from one modality to the other. They more often rely on anatomical cues that are visible both by light and electron microscopy. We present here a simple workflow where multicellular specimens are embedded in minimal amounts of resin, exposing their surface topology that can be imaged by scanning electron microscopy (SEM). LM and SEM both benefit from a large field of view that can cover whole model organisms. As a result, targeting specific anatomic locations by focused ion beam-SEM (FIB-SEM) tomography becomes straightforward. We illustrate this application on three different model organisms, used in our laboratory: the zebrafish embryo Danio rerio, the marine worm Platynereis dumerilii, and the dauer larva of the nematode Caenorhabditis elegans. Here we focus on the experimental steps to reduce the amount of resin covering the samples and to image the specimens inside an FIB-SEM. We expect this approach to have widespread applications for volume electron microscopy on multiple model organisms. Copyright © 2017 Elsevier Inc. All rights reserved.
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Integration of Correlative Raman microscopy in a dual beam FIB-SEM J. of Raman Spectroscopy
Timmermans, Frank Jan; Liszka, B.; Lenferink, Aufrid T.M.; van Wolferen, Hendricus A.G.M.; Otto, Cornelis
2016-01-01
We present an integrated confocal Raman microscope in a focused ion beam scanning electron microscope (FIB SEM). The integrated system enables correlative Raman and electron microscopic analysis combined with focused ion beam sample modification on the same sample location. This provides new
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Karwacki, L.|info:eu-repo/dai/nl/304824283; de Winter, D.A.M.|info:eu-repo/dai/nl/304838616; Aramburo, L.R.; Lebbink, M.N.|info:eu-repo/dai/nl/304834246; Post, J.A.|info:eu-repo/dai/nl/074120050; Drury, M.R.|info:eu-repo/dai/nl/304829315; Weckhuysen, B.M.|info:eu-repo/dai/nl/285484397
2011-01-01
Break on through: Steaming-induced mesopores of individual ZSM-5 crystals were studied by a combination of focused ion beam (FIB) and scanning electron microscopy (SEM) tomography (see picture). In this manner, quantitative insight into the width, length, morphology, and distribution of mesopores
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Newbury, Dale E.; Ritchie, Nicholas W. M.
2014-09-01
Quantitative electron-excited x-ray microanalysis by scanning electron microscopy/silicon drift detector energy dispersive x-ray spectrometry (SEM/SDD-EDS) is capable of achieving high accuracy and high precision equivalent to that of the high spectral resolution wavelength dispersive x-ray spectrometer even when severe peak interference occurs. The throughput of the SDD-EDS enables high count spectra to be measured that are stable in calibration and resolution (peak shape) across the full deadtime range. With this high spectral stability, multiple linear least squares peak fitting is successful for separating overlapping peaks and spectral background. Careful specimen preparation is necessary to remove topography on unknowns and standards. The standards-based matrix correction procedure embedded in the NIST DTSA-II software engine returns quantitative results supported by a complete error budget, including estimates of the uncertainties from measurement statistics and from the physical basis of the matrix corrections. NIST DTSA-II is available free for Java-platforms at: http://www.cstl.nist.gov/div837/837.02/epq/dtsa2/index.html).
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Directory of Open Access Journals (Sweden)
Murat Enoz
2009-10-01
Full Text Available AIM: To describe the bacterial and fungal organisms in otitis externa patients without other risk factors for fungal infections. STUDY DESIGN: Cross sectional cohort descriptive study. MATERIALS AND METHODS: Ear swabs were obtained from 362 patients aged 1 to 55 years old with clinically diagnosed otitis externa in Erzurum, Turkey, between January 2006 and April 2007, and cultured for aerobic and anaerobic bacteria and fungi, using EMB, 5% sheep's blood, chocolate agar, anaerobic blood agar plate, thioglycollate broth and sabaroud agar using standard microbiological technique to diagnose isolates. RESULTS: 219 cultures were positive and a total of 267 isolates were obtained. Of the isolates, 68.16% (n: 182 were aerobic or facultative bacteria, 1.12 % (3 were anaerobic bacteria, 30.71 % (82 were fungi and 17.5 % (38 were polymicrobial infections. CONCLUSION: Fungal organisms especially Candida species may be isolated from ears of otitis externa patients without fungal infection risk factors such as ear self-cleaning, local antimicrobial, antifungal or corticosteroid drops or systemic antimicrobial or antifungal agents within the preceding week. Bacterial and fungal cultures may be recommended, and anti-fungal agents may be added, to treatment regimens in patients with otitis externa.OBJETIVO: Descrever fungos e bactérias presentes em pacientes com otite externa sem fator de risco para infecções fúngicas. FORMA DE ESTUDO: Estudo descritivo de coorte transversal. MATERIAIS E MÉTODOS: Amostras por raspagem de cotonetes (swabs no ouvido foram obtidas de 362 pacientes com idades entre 1 e 55 anos, com diagnóstico clínico de otite externa em Erzurum, Turquia, entre janeiro de 2006 e abril de 2007. Essas amostras foram cultivadas em meio de cultura, 5% de sangue de ovelha, ágar chocolate, ágar sangue anaeróbio, banho em tioglicolato e ágar Saboroud, usando técnicas padrão de microbiologia para identificar os isolados. RESULTADOS: Obtivemos
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A SEM-correlation of the anatomy of the vitreous body: making visible the invisible.
Jongebloed, W L; Humalda, D; Worst, J F
1986-12-30
The naked human vitreous (sclera, iris and cornea removed) suspended in water does not reveal inner structures. After ink injection into the vitreous, the presence of different compartments and the existence of cisterns becomes evident. A concept of the internal system of cisterns is given on the basis of stereoscopic-lightmicroscopic images. An attempt is made to correlate images of the complete vitreous body, obtained with a stereo-lightmicroscope, with images of segments of cisternal walls produced with a scanning electron-microscope (SEM). A comparison is made between SEM-images of the vitreous bodies of human and rabbit eyes.
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Kiani, M A; Sim, K S; Nia, M E; Tso, C P
2015-05-01
A new technique based on cubic spline interpolation with Savitzky-Golay smoothing using weighted least squares error filter is enhanced for scanning electron microscope (SEM) images. A diversity of sample images is captured and the performance is found to be better when compared with the moving average and the standard median filters, with respect to eliminating noise. This technique can be implemented efficiently on real-time SEM images, with all mandatory data for processing obtained from a single image. Noise in images, and particularly in SEM images, are undesirable. A new noise reduction technique, based on cubic spline interpolation with Savitzky-Golay and weighted least squares error method, is developed. We apply the combined technique to single image signal-to-noise ratio estimation and noise reduction for SEM imaging system. This autocorrelation-based technique requires image details to be correlated over a few pixels, whereas the noise is assumed to be uncorrelated from pixel to pixel. The noise component is derived from the difference between the image autocorrelation at zero offset, and the estimation of the corresponding original autocorrelation. In the few test cases involving different images, the efficiency of the developed noise reduction filter is proved to be significantly better than those obtained from the other methods. Noise can be reduced efficiently with appropriate choice of scan rate from real-time SEM images, without generating corruption or increasing scanning time. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.
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Automated CD-SEM recipe creation technology for mass production using CAD data
Kawahara, Toshikazu; Yoshida, Masamichi; Tanaka, Masashi; Ido, Sanyu; Nakano, Hiroyuki; Adachi, Naokaka; Abe, Yuichi; Nagatomo, Wataru
2011-03-01
Critical Dimension Scanning Electron Microscope (CD-SEM) recipe creation needs sample preparation necessary for matching pattern registration, and recipe creation on CD-SEM using the sample, which hinders the reduction in test production cost and time in semiconductor manufacturing factories. From the perspective of cost reduction and improvement of the test production efficiency, automated CD-SEM recipe creation without the sample preparation and the manual operation has been important in the production lines. For the automated CD-SEM recipe creation, we have introduced RecipeDirector (RD) that enables the recipe creation by using Computer-Aided Design (CAD) data and text data that includes measurement information. We have developed a system that automatically creates the CAD data and the text data necessary for the recipe creation on RD; and, for the elimination of the manual operation, we have enhanced RD so that all measurement information can be specified in the text data. As a result, we have established an automated CD-SEM recipe creation system without the sample preparation and the manual operation. For the introduction of the CD-SEM recipe creation system using RD to the production lines, the accuracy of the pattern matching was an issue. The shape of design templates for the matching created from the CAD data was different from that of SEM images in vision. Thus, a development of robust pattern matching algorithm that considers the shape difference was needed. The addition of image processing of the templates for the matching and shape processing of the CAD patterns in the lower layer has enabled the robust pattern matching. This paper describes the automated CD-SEM recipe creation technology for the production lines without the sample preparation and the manual operation using RD applied in Sony Semiconductor Kyusyu Corporation Kumamoto Technology Center (SCK Corporation Kumamoto TEC).
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Directory of Open Access Journals (Sweden)
Mikael L.D.L. Tolentino
2014-07-01
Full Text Available Foram utilizados 42 ovinos sem raça definida, divididos segundo a configuração escrotal. Destes animais, 12 foram utilizados na investigação da biometria testicular e histologia da pele escrotal. Os demais foram destinados ao estudo do funículo espermático. Os animais foram agrupados em um grupo de 21 animais sem bipartição escrotal (GEI e 21 com bipartição escrotal, (GEII, esta não atingindo 50% do comprimento do eixo longitudinal do escroto. Em cada grupo, em 6 animais foram coletados fragmentos da pele do escroto e em 5 do funículo espermáticos, e processados em rotina histológica e analisados em microscopia de luz; e em 10 foram injetados látex na artéria testicular para obtenção de moldes vasculares e obtenção do comprimento da artéria. Quando comparados os grupos GEI e GEII, não foram encontradas diferenças estatísticas significativas (p<0,05 entre a espessura do escroto (epiderme e derme, constituição histológica da pele escrotal, número de glândulas sudoríparas por área, comprimento do funículo espermático ou parâmetros biométricos testiculares. Entretanto, o comprimento total das artérias testiculares do GEI foi maior do que o GEII (p<0,05. Concluiu-se, com base nos parâmetros morfológicos analisados, que a bipartição escrotal em ovinos não influenciou na estrutura da pele, funículo ou biometria testicular quando comparado aos animais que não apresentavam esta característica. Outros estudos merecem atenção para desmistificar o porquê do aparecimento dessa característica em ovinos e se esta característica é ou não desejável para melhoria na produção desses animais em regiões de clima quente.
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Ball, A D; Job, P A; Walker, A E L
2017-08-01
The method we present here uses a scanning electron microscope programmed via macros to automatically capture dozens of images at suitable angles to generate accurate, detailed three-dimensional (3D) surface models with micron-scale resolution. We demonstrate that it is possible to use these Scanning Electron Microscope (SEM) images in conjunction with commercially available software originally developed for photogrammetry reconstructions from Digital Single Lens Reflex (DSLR) cameras and to reconstruct 3D models of the specimen. These 3D models can then be exported as polygon meshes and eventually 3D printed. This technique offers the potential to obtain data suitable to reconstruct very tiny features (e.g. diatoms, butterfly scales and mineral fabrics) at nanometre resolution. Ultimately, we foresee this as being a useful tool for better understanding spatial relationships at very high resolution. However, our motivation is also to use it to produce 3D models to be used in public outreach events and exhibitions, especially for the blind or partially sighted. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.
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International Nuclear Information System (INIS)
Klaver, Jop; Desbois, Guillaume; Urai, Janos L.
2013-01-01
This contribution focuses on the characterization of porosity in low porous shale using a broad ion beam (BIB) polishing technique combined with a conventional scanning electron microscopy (SEM). Porosity was traced in certain representative elementary areas (REA) and pores detected are segmented from mosaics of secondary electron (SE) images. Traced pores could be classified into two major pore-size classes. Relative large pores (> 0.5 μm 2 ) were found in the organic matter and matrix. They contribute strongly to the overall porosity con-tent of the shale. Nevertheless the far majority of the pores traced have equivalent radius less than 400 nm. Including the latter pore class, the imaged porosity from both samples gives similar results in the order of < 1 %. (authors)
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DEFF Research Database (Denmark)
Bariani, Paolo; De Chiffre, Leonardo; Hansen, Hans Nørgaard
2005-01-01
An investigation was carried out concerning the traceability of dimensional measurements performed with the scanning electron microscope (SEM) using reconstruction of surface topography through stereo-photogrammetry. A theoretical description of the effects that the main instrumental variables...... with the scanning electron microscope (SEM) using reconstruction of surface topography through stereo-photogrammetry. A theoretical description of the effects that the main instrumental variables and measurement parameters have on the reconstruction accuracy of any point on the surface of the object being imaged......-dimensional topography of the type C roughness standards showed good agreement with the nominal profile wavelength values. An investigation was carried out concerning the traceability of dimensional measurements performed with the scanning electron microscope (SEM) using reconstruction of surface topography through...
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Directory of Open Access Journals (Sweden)
Ivonete Alves Bakke
2007-03-01
Full Text Available The objective of this work was to compare forage production and quality of thorny and thornless "jurema-preta" (Mimosa tenuiflora (Willd. Poiret in a dense planted stand, subjected to annual pruning of fine branches, in Patos, PB, Brazil. The experiment consisted of two treatments (thornless and thorny "jurema-preta" in a complete randomized block design, with ten replicates of two linear plots subdivided in time. Forage mass and chemical composition of fine branches and the basal diameter of plants were measured during five years. Pruning decreased (p0.05 for both genotypes. This roughage fodder (minimum NDF and ADF averages were 56±1.1% and 43±1.0%, respectively had low P and K concentrations. Its average crude protein content was greater than 9.9±0.5%, which exceeds the minimum necessary for animal maintenance. Both "jurema-preta" genotypes tolerated pruning of fine branches and contributed with a significant amount of roughage fodder for animal maintenance in the dry season.O objetivo deste trabalho foi comparar a produção e qualidade da forragem de jurema-preta (Mimosa tenuiflora (Willd. Poiret com e sem acúleos, em plantio adensado, submetida ao corte anual dos ramos finos, em Patos, PB. Utilizou-se delineamento em blocos casualizados, com dois tratamentos (plantas sem acúleos e plantas com acúleos, com dez repetições de duas parcelas lineares subdivididas no tempo. A produção e composição química da forragem de ramos finos e o diâmetro basal das plantas foram medidos durante cinco anos. A poda diminuiu (p0,05 para os dois fenótipos. Este volumoso - valores médios mínimos para FDN e FDA: 56±1,1% e 43±1,1%, respectivamente - mostrou-se pobre em P e K. Seu teor médio de proteína bruta acima de 9,9±0,5% superou o mínimo necessário para a manutenção animal. Os dois genótipos toleraram a poda dos ramos e contribuíram com uma quantidade significativa de volumoso para a manutenção de ruminantes na estação seca.
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Integration of a high-NA light microscope in a scanning electron microscope.
Zonnevylle, A C; Van Tol, R F C; Liv, N; Narvaez, A C; Effting, A P J; Kruit, P; Hoogenboom, J P
2013-10-01
We present an integrated light-electron microscope in which an inverted high-NA objective lens is positioned inside a scanning electron microscope (SEM). The SEM objective lens and the light objective lens have a common axis and focal plane, allowing high-resolution optical microscopy and scanning electron microscopy on the same area of a sample simultaneously. Components for light illumination and detection can be mounted outside the vacuum, enabling flexibility in the construction of the light microscope. The light objective lens can be positioned underneath the SEM objective lens during operation for sub-10 μm alignment of the fields of view of the light and electron microscopes. We demonstrate in situ epifluorescence microscopy in the SEM with a numerical aperture of 1.4 using vacuum-compatible immersion oil. For a 40-nm-diameter fluorescent polymer nanoparticle, an intensity profile with a FWHM of 380 nm is measured whereas the SEM performance is uncompromised. The integrated instrument may offer new possibilities for correlative light and electron microscopy in the life sciences as well as in physics and chemistry. © 2013 The Authors Journal of Microscopy © 2013 Royal Microscopical Society.
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Interpretation of secondary electron images obtained using a low vacuum SEM
International Nuclear Information System (INIS)
Toth, M.; Thiel, B.L.; Donald, A.M.
2003-01-01
Charging of insulators in a variable pressure environment was investigated in the context of secondary electron (SE) image formation. Sample charging and ionized gas molecules present in a low vacuum specimen chamber can give rise to SE image contrast. 'Charge-induced' SE contrast reflects lateral variations in the charge state of a sample caused by electron irradiation during and prior to image acquisition. This contrast corresponds to SE emission current alterations produced by sub-surface charge deposited by the electron beam. 'Ion-induced' contrast results from spatial inhomogeneities in the extent of SE signal inhibition caused by ions in the gaseous environment of a low vacuum scanning electron microscope (SEM). The inhomogeneities are caused by ion focusing onto regions of a sample that correspond to local minima in the magnitude of the surface potential (generated by sub-surface trapped charge), or topographic asperities. The two types of contrast exhibit characteristic dependencies on microscope operating parameters such as scan speed, beam current, gas pressure, detector bias and working distance. These dependencies, explained in terms of the behavior of the gaseous environment and sample charging, can serve as a basis for a correct interpretation of SE images obtained using a low vacuum SEM
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Directory of Open Access Journals (Sweden)
Fernanda Marcondes Ribas
Full Text Available OBJETIVO: Avaliar por exame de tomografia computadorizada de pacientes submetidos à derivação gastrojejunal em Y-de-Roux, sem anel, para tratamento de obesidade mórbida. MÉTODOS: Estudaram-se 40 pacientes, encaminhados ao serviço de tomografia do Hospital Universitário Evangélico de Curitiba para avaliação diagnóstica. Encontravam-se em pós-operatório de cirurgia bariátrica tendo sido operados no mesmo hospital. Foram incluídos pacientes submetidos à operação laparoscópica com sintomas que necessitavam de avaliação tomográfica diagnóstica. Excluíram-se pacientes que tinham sido submetidos à cirurgia bariátrica por outras técnicas cirúrgicas; que tinham sido operados por outra equipe; que não concordassem com a administração de contraste iodado por via oral ou endovenosa; e que excediam o limite de peso da mesa de exame. Para análise estatística utilizou-se a média das variáveis. RESULTADOS: Os pacientes apresentaram-se com idade entre 23 a 70 anos e eram 11 homens e 29 mulheres. Não houve alterações extra-abdominais detectáveis pela tomografia de abdômen total; dos 40 pacientes avaliados, 30 apresentavam achados tomográficos dentro do limite da normalidade. A presença de estenose na anastomose gastrojejunal foi encontrada em um paciente; hérnia interna ocorreu em cinco; fístula anastomótica em um e abcesso em três dos pacientes estudados. CONCLUSÃO: A tomografia de abdome total não conseguiu informar a causa dos sintomas dos pacientes operados em 87,5% dos pacientes que procuraram re-avaliação médica por sintomas pós-operatórios da cirurgia bariátrica.
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Directory of Open Access Journals (Sweden)
Ricardo Ierusalimschy
2002-09-01
Full Text Available Com o objetivo de estudar a distribuição de fatores desencadeantes de migrânea em uma população determinada, foram avaliados, através de entrevista pessoal, 100 pacientes que preenchiam os critérios diagnósticos para migrânea sem aura propostos pela Sociedade Internacional de Cefaléia. O estresse foi o desencadeante mais citado, respondendo pelo surgimento de crises de migrânea em 76% dos pacientes. Em seguida, em ordem de frequência decrescente, foram citados: estímulos sensoriais (75%, privação do sono (49%, jejum (48%, fatores ambientais (47%, alimentos (46%, menstruação (39%, fadiga (35%, bebidas alcoólicas (28%, sono prolongado (27%, cafeína (22%, esforço físico (20%, trauma craniano (20%, viagens (4%, atividade sexual (3%, medicamentos (2%, os movimentos do pescoço (2%, tabagismo (1% e uso de travesseiro baixo (1%. Conclui-se que determinados fatores parecem desempenhar papel importante na precipitação da migrânea.To study the distribution of triggers of migraine in a selected population, 100 patients who fulfilled the diagnostic criteria for migraine without aura as proposed by the International Headache Societywere evaluated by means of a personal interview. Stress was the most cited trigger, triggering migraine in 76%. Afterwards, in descending order of frequency, were cited sensorial stimuli (75%, sleep deprivation (49%, hunger (48%, environmental factors (47%, food (46%, menses (39%, fatigue (35%, alcohol (28%, sleep excess (27%, cafeine (22%, physical exertion (20%, head trauma (20%, trips (4%, sexual activity (3%, medications (2%, neck movements (2%, smoking (1% and the use of a low pillow (1%. It is concluded that certain factors seem to play an important role in the triggering of migraine.
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Directory of Open Access Journals (Sweden)
Solange Bordignon
1996-12-01
Full Text Available O resultado clínico pós-operatório (p.o. tardio da reconstrução da valva mitral sem suporte em crianças e adolescentes é analisado através da observação de uma série de 70 pacientes operados. Objetivou-se acompanhar a evolução clínica tardia após o tratamento de insuficiência mitral pelas técnicas reparadoras nos pacientes em fase de crescimento, avaliar a eficácia, a durabilidade e a reprodutibilidade do procedimento, bem como morbidade e mortalidade nas fases hospitalar e tardia. Consideraram-se, ainda, os resultados em relação à etiologia da doença e as causas de falha do método. De 1977 a 1995, foram operados 70 pacientes, sendo 36 casos do sexo feminino e 34 do masculino. A média de idade foi de 12,4 ± 4,8 anos (6m a 18a. Houve predomínio da etiologia reumática (71,4% sobre a congênita (18,6%, a degeneração mixomatosa (8,6% e a infecciosa (1,4%. A classe funcional pré-operatória era 11 em 32 (45,7% casos, 111 em 18 (25,7% casos e IV em 20 (28,6% casos. A técnica cirúrgica utilizada foi a anuloplastia simples tipo Wooler isolada em 58 (82,9% casos e associada a encurtamento de cordoalha em 12(17,1%. Em 21 (30% pacientes foram realizados procedimentos associados. O período de acompanhamento foi de 7 m a 17 anos, no p.o. A mortalidade hospitalar foi 4,3%. Regurgitação mitral foi descrita no intra-operatório em 21,4%. Sopro sistólico de regurgitação mitral residual foi notado em 35 (49,9% pacientes, a maioria sem repercussão hemodinâmica. A classe funcional pós-operatória foi I em 73,9%, II em 21,7% e III em 4,4%. As curvas de análise atuarial mostraram aos 5 e 10 anos, respectivamente, probabilidade de sobrevida global de 89% e 79% e estimativa de permanecer livre de eventos cirúrgicos no período de 87% e 61 % no grupo total, 88% e 56% no grupo de etiologia reumática e 91 % no grupo de etiologia congênita para 5 e 10 anos. A insuficiência mitral pode ser tratada efetivamente por anuloplastia
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Directory of Open Access Journals (Sweden)
M. Voss
1998-03-01
Full Text Available Entre os macronutrientes, o fósforo é o que com maior freqüência proporciona aumento na produtividade das culturas. Tem-se demonstrado que a obtenção de nitrogênio por algumas das simbioses rizóbio-leguminosas exige teores maiores de fósforo do que a planta adubada com nitrogênio. Visando aumentar a eficiência no aproveitamento de fósforo no solo sem incrementar a dose de adubação, testaram-se modos de localização de adubo com fosfato solúvel para as culturas de feijão e de grão-de-bico. O feijão, em ensaio instalado em Jaguapitã (PR, foi semeado, em outubro de 1986, em um Latossolo Vermelho-Escuro com 113 g kg-1 de argila e 2,2 mg dm-3 de P. O adubo fosfatado foi distribuído a 7 cm, e as sementes a 3 cm de profundidade, ambos no sulco de semeadura. Comparou-se a adubação no sulco com a adubação em covas, em doses de 50 e de 100 kg ha-1 de P2O5, como superfosfato triplo (SFT. Incluiu-se um tratamento extra com 25 kg ha-1 de P2O5 em covas, além de testemunha sem adubação fosfatada. O feijão foi semeado em covas. O ensaio com grão-de-bico foi instalado em Londrina (PR, em junho de 1987, em um Latossolo Roxo com 760 g kg-1 de argila e 3,6 mg dm-3 de P. A adubação foi feita a 7 cm de profundidade, e a semeadura a 3 cm de profundidade. Nesse ensaio, foram testados, nas parcelas, os tratamentos: testemunha sem rizóbio, inoculação com rizóbio e sem inoculação + 30 kg ha-1 de N e, nas subparcelas, a adubação fosfatada em linha ou em covas. O grão-de-bico foi semeado em linha. Foram avaliados os teores de N, P, Zn e Mn nas folhas de feijão, bem como a produtividade e a nodulação de feijão e de grão-de-bico. Não houve nodulação em feijão e a tendência para maior nodulação em grão-de-bico, quando a adubação foi aplicada em covas, não foi significativa. Houve aumento de cerca de 40% no rendimento do feijão e de 3l% no de grão-de-bico pela adubação em covas, em relação à adubação em linha. Em
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Jiang, Chenchen; Lu, Haojian; Zhang, Hongti; Shen, Yajing; Lu, Yang
2017-01-01
In the past decades, in situ scanning electron microscopy (SEM) has become a powerful technique for the experimental study of low-dimensional (1D/2D) nanomaterials, since it can provide unprecedented details for individual nanostructures upon mechanical and electrical stimulus and thus uncover the fundamental deformation and failure mechanisms for their device applications. In this overview, we summarized recent developments on in situ SEM-based mechanical and electrical characterization techniques including tensile, compression, bending, and electrical property probing on individual nanostructures, as well as the state-of-the-art electromechanical coupling analysis. In addition, the advantages and disadvantages of in situ SEM tests were also discussed with some possible solutions to address the challenges. Furthermore, critical challenges were also discussed for the development and design of robust in situ SEM characterization platform with higher resolution and wider range of samples. These experimental efforts have offered in-depth understanding on the mechanical and electrical properties of low-dimensional nanomaterial components and given guidelines for their further structural and functional applications.
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Directory of Open Access Journals (Sweden)
Chenchen Jiang
2017-01-01
Full Text Available In the past decades, in situ scanning electron microscopy (SEM has become a powerful technique for the experimental study of low-dimensional (1D/2D nanomaterials, since it can provide unprecedented details for individual nanostructures upon mechanical and electrical stimulus and thus uncover the fundamental deformation and failure mechanisms for their device applications. In this overview, we summarized recent developments on in situ SEM-based mechanical and electrical characterization techniques including tensile, compression, bending, and electrical property probing on individual nanostructures, as well as the state-of-the-art electromechanical coupling analysis. In addition, the advantages and disadvantages of in situ SEM tests were also discussed with some possible solutions to address the challenges. Furthermore, critical challenges were also discussed for the development and design of robust in situ SEM characterization platform with higher resolution and wider range of samples. These experimental efforts have offered in-depth understanding on the mechanical and electrical properties of low-dimensional nanomaterial components and given guidelines for their further structural and functional applications.
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Imaging of Norway spruce early somatic embryos with the ESEM, Cryo-SEM and laser scanning microscope
Czech Academy of Sciences Publication Activity Database
Neděla, Vilém; Hřib, Jiří; Havel, L.; Hudec, Jiří; Runštuk, Jiří
2016-01-01
Roč. 84, May 2016 (2016), s. 67-71 ISSN 0968-4328 R&D Projects: GA ČR(CZ) GA14-22777S Institutional support: RVO:68081731 Keywords : ESEM * Cryo-SEM * bright field/dark field microscopy * extracellular matrix * Picea abies * somatic embryogenesis Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.980, year: 2016
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DEFF Research Database (Denmark)
Carli, Lorenzo; Genta, Gianfranco; Cantatore, Angela
2010-01-01
The work deals with an experimental investigation on the influence of three Scanning Electron Microscope (SEM) instrument settings, accelerating voltage, spot size and magnification, on the image formation process. Pixel size and nonlinearity were chosen as output parameters related to image...... quality and resolution. A silicon grating calibrated artifact was employed to investigate qualitatively and quantitatively, through a designed experiment approach, the parameters relevance. SEM magnification was found to account by far for the largest contribution on both parameters under consideration...
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Does Your SEM Really Tell the Truth?-How Would You Know? Part 4: Charging and its Mitigation.
Postek, Michael T; Vladár, András E
2015-01-01
This is the fourth part of a series of tutorial papers discussing various causes of measurement uncertainty in scanned particle beam instruments, and some of the solutions researched and developed at NIST and other research institutions. Scanned particle beam instruments, especially the scanning electron microscope (SEM), have gone through tremendous evolution to become indispensable tools for many and diverse scientifc and industrial applications. These improvements have significantly enhanced their performance and made them far easier to operate. But, the ease of operation has also fostered operator complacency. In addition, the user-friendliness has reduced the apparent need for extensive operator training. Unfortunately, this has led to the idea that the SEM is just another expensive "digital camera" or another peripheral device connected to a computer and that all of the problems in obtaining good quality images and data have been solved. Hence, one using these instruments may be lulled into thinking that all of the potential pitfalls have been fully eliminated and believing that, everything one sees on the micrograph is always correct. But, as described in this and the earlier papers, this may not be the case. Care must always be taken when reliable quantitative data are being sought. The first paper in this series discussed some of the issues related to signal generation in the SEM, including instrument calibration, electron beam-sample interactions and the need for physics-based modeling to understand the actual image formation mechanisms to properly interpret SEM images. The second paper has discussed another major issue confronting the microscopist: specimen contamination and methods to eliminate it. The third paper discussed mechanical vibration and stage drift and some useful solutions to mitigate the problems caused by them, and here, in this the fourth contribution, the issues related to specimen "charging" and its mitigation are discussed relative to
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DEFF Research Database (Denmark)
Fernandez-Buenaga, Roberto; Alio, Jorge L.; Ramirez, Jose M.
2015-01-01
Purpose To compare variations in surface morphology, as studied by scanning electron microscopy (SEM), of explanted intraocular lenses (IOLs) concerning the cause leading to the explantation surgery. Methods In this prospective multicenter study, explanted IOLs were analyzed by SEM and energy...... explanted due to dislocation demonstrated calcifications in 8 lenses (50%), salt precipitates in 6 cases (37.5%), and erythrocytes and fibrosis/fibroblasts in 2 cases (12.5%). In the refractive error cases, the SEM showed proteins in 5 cases (45.5%) and salt precipitates in 4 lenses (36.4%). In IOL...... opacification, the findings were calcifications in 2 of the 3 lenses (66.6%) and proteins in 2 lenses (66.6%). Conclusions A marked variation in surface changes was observed by SEM. Findings did not correlate with cause for explantation. Scanning electron microscopy is a useful tool that provides exclusive...
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Atmospheric scanning electron microscope for correlative microscopy.
Morrison, Ian E G; Dennison, Clare L; Nishiyama, Hidetoshi; Suga, Mitsuo; Sato, Chikara; Yarwood, Andrew; O'Toole, Peter J
2012-01-01
The JEOL ClairScope is the first truly correlative scanning electron and optical microscope. An inverted scanning electron microscope (SEM) column allows electron images of wet samples to be obtained in ambient conditions in a biological culture dish, via a silicon nitride film window in the base. A standard inverted optical microscope positioned above the dish holder can be used to take reflected light and epifluorescence images of the same sample, under atmospheric conditions that permit biochemical modifications. For SEM, the open dish allows successive staining operations to be performed without moving the holder. The standard optical color camera used for fluorescence imaging can be exchanged for a high-sensitivity monochrome camera to detect low-intensity fluorescence signals, and also cathodoluminescence emission from nanophosphor particles. If these particles are applied to the sample at a suitable density, they can greatly assist the task of perfecting the correlation between the optical and electron images. Copyright © 2012 Elsevier Inc. All rights reserved.
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Matérias estranhas em canela em pó e páprica em pó, comercializadas no estado de São Paulo
Directory of Open Access Journals (Sweden)
CORREIA Marlene
2000-01-01
Full Text Available Com objetivos de padronizar metodologias para matérias estranhas em canela em pó e páprica em pó e de avaliar as condições higiênicas desses condimentos, foram adquiridas, no período de agosto a novembro de 1998, 78 amostras de canela em pó e 56 de páprica em pó, em estabelecimentos comerciais de seis cidades do Estado de São Paulo. Foram utilizados métodos da Association of Official Analytical Chemists International (AOAC - 1995, 16.14.12/968.38b para canela em pó e 16.14.22/977.25B para páprica em pó. Os métodos mostraram-se adequados, sem resíduos interferentes no papel de filtro que dificultasse o diagnóstico da análise e viáveis de serem utilizados nos laboratórios de Microscopia de Alimentos. Os resultados obtidos indicaram 100% das amostras contendo fragmentos de insetos; pêlos de roedor foram isolados em 73,1% de amostras de canela em pó e 34,0% de páprica em pó, enquanto ácaros mortos apareceram, respectivamente, em 37,2% e 12,5% de amostras. É necessário revisão da legislação de alimentos em vigor, com o estabelecimento de níveis de tolerância para fragmentos de insetos.
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Variable-temperature independently driven four-tip scanning tunneling microscope
International Nuclear Information System (INIS)
Hobara, Rei; Nagamura, Naoka; Hasegawa, Shuji; Matsuda, Iwao; Yamamoto, Yuko; Miyatake, Yutaka; Nagamura, Toshihiko
2007-01-01
The authors have developed an ultrahigh vacuum (UHV) variable-temperature four-tip scanning tunneling microscope (STM), operating from room temperature down to 7 K, combined with a scanning electron microscope (SEM). Four STM tips are mechanically and electrically independent and capable of positioning in arbitrary configurations in nanometer precision. An integrated controller system for both of the multitip STM and SEM with a single computer has also been developed, which enables the four tips to operate either for STM imaging independently and for four-point probe (4PP) conductivity measurements cooperatively. Atomic-resolution STM images of graphite were obtained simultaneously by the four tips. Conductivity measurements by 4PP method were also performed at various temperatures with the four tips in square arrangement with direct contact to the sample surface
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Stephant, Nicolas; Grissa, Rabeb; Guillou, Fanch; Bretaudeau, Mickaël; Borjon-Piron, Yann; Guillet, Jacques; Moreau, Philippe
2018-04-18
The surface of some materials reacts very quickly on contact with air, either because it is oxidized or because it gets humidity from the air. For the sake of original surface observation by scanning electron microscopy (SEM), we conceived an airtight transfer box to keep the samples under vacuum from the place of manufacturing to the SEM chamber. This object is designed to fit in all the models of SEM including those provided with an airlock chamber. The design is voluntarily simplified to allow the manufacturing of the object by a standard mechanical workshop. The transfer box can be easily opened by gravity inside the SEM and allows the preservation of the best vacuum inside, before opening. SEM images and energy dispersive spectroscopy (EDX) analyses of metallic lithium and sodium samples are presented prior and after exposure to the air. X-ray Photoelectron Spectroscopy (XPS) analyses of all samples are also discussed in order to investigate the chemical environments of the detected elements. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Characterization of Yeast Biofilm by Cryo-SEM and FIB-SEM
Czech Academy of Sciences Publication Activity Database
Hrubanová, Kamila; Nebesářová, Jana; Růžička, F.; Dluhoš, J.; Krzyžánek, Vladislav
2013-01-01
Roč. 19, S2 (2013), s. 226-227 ISSN 1431-9276 R&D Projects: GA MŠk EE.2.3.20.0103; GA TA ČR TE01020118; GA ČR GAP205/11/1687 Institutional support: RVO:68081731 ; RVO:60077344 Keywords : yeast biofilm * cryo-SEM * FIB-SEM Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.757, year: 2013
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Directory of Open Access Journals (Sweden)
Dênis Marinho da Silva Brandão
2009-01-01
Full Text Available OBJETIVO: Analisar a capacidade funcional e a qualidade de vida em indivíduos idosos após AVE Isquêmico, comparando sujeitos com e sem disfagia. MÉTODOS: Estudo transversal em 60 sujeitos idosos após AVE, sendo 30 com disfagia e 30 sem disfagia. Para avaliar o estado cognitivo dos pacientes foi utilizado o Mini-Mental. As escalas utilizados foram: de KATZ, de Lawton, de Barthel e o SF-36. RESULTADOS: A capacidade funcional foi similar nos dois grupos estudados. No SF-36, o grupo sem disfagia apresentou mais dor e melhor estado geral de saúde. Na capacidade funcional, limitação por aspectos físicos, estado geral de saúde, vitalidade, aspectos sociais, limitações por aspectos emocionais e saúde mental os grupos foram similares. Entre os homens, em todos os instrumentos, encontrou-se capacidade funcional similar. Entre as mulheres, a capacidade funcional foi similar enquanto que, na qualidade de vida, o domínio vitalidade do grupo sem disfagia foi maior. Não houve diferença quanto à renda econômica baixa, tanto na capacidade funcional quanto na qualidade de vida. Também não houve diferença entre os dois grupos quanto a ter ou não cuidador. CONCLUSÕES: 1 A capacidade funcional foi similar nos dois grupos estudados. 2 O grupo sem disfagia apresentou melhor estado geral de saúde.OBJECTIVE: The objective was to analyze the functional capacity and quality of life of elderly individuals with ischemic stroke comparing these with and without dysphagia. METHOD: Cross sectional study was realized in 60 elderly individuals after ischemic stroke, 30 with dysphagia and 30 without. Their cognitive state was evaluated with the Mini-Mental test. The scales used were: KATZ, Lawton, Barthel and SF-36. RESULTS: The functional capacity was similar in both groups studied. In the SF-36, the group without dysphagia presented more pain and a better general health. Functional capacity, physical limitations those due to emotional aspects, general
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Directory of Open Access Journals (Sweden)
Renato Rocha Souza
2011-05-01
Full Text Available O termo "semântica" tem sido amplamente utilizado nos últimos anos em diversas áreas de pesquisa e, em particular, em áreas relacionadas à tecnologia da informação. Um dos motivadores de tal apropriação é a visão da Web Semântica, originada na expansão da web e nas limitações dos instrumentos de busca baseados em sintaxe. Cabe questionar, entretanto, qual é esta "semântica" de que trata a Web Semântica, uma vez que o estudo do assunto é complexo e controverso. O presente artigo se insere nesse contexto, analisando o que é semântica, discutindo-a no âmbito da tecnologia da informação e propondo alternativas interpretativas. Avalia-se criticamente um espectro, o qual propõe a ordenação de instrumentos (modelos, linguagens, estruturas taxonômicas, etc. de acordo com uma escala semântica. Espera-se tornar claro o uso do termo em contextos diversos, bem como propor um novo espectro a partir das considerações do presente artigo.The term “semantics” has been used over the past years in several areas of research and, more specifically, in those related to information technology. One reason for that appropriation is the Semantic Web vision, which originated from the expansion of the web and the inherent limitations of the syntax-based search engines. However, it is reasonable to demand an explanation about which is the semantics addressed in the Semantic Web since the study of the subject is complex and controversial. The present article aims to make a contribution towards this sense, analyzing what semantic is, discussing it within the scope of information technology and proposing explanatory alternatives. We intend to critically evaluate a spectrum that suggests a classification of instruments (models, languages, taxonomic structures, etc in a semantic-based scale of graduated rates. We hope to provide a better understanding about the use of the term in different contexts, as well as offer a new spectrum from the
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Directory of Open Access Journals (Sweden)
Délio Marques Conde
2012-12-01
Full Text Available OBJECTIVE: The values of bone mineral density (BMD were compared in postmenopausal women with and without breast cancer. METHODS: A cross-sectional study was conducted, including 51 breast cancer survivors (BCS and 71 women without breast cancer, who were non-users of hormone therapy, tamoxifen, or aromatase inhibitors. BMD T-scores and measurements in grams per centimeter squared (g/cm² were obtained at the femoral neck, trochanter, Ward's triangle, and lumbar spine. Osteopenia and osteoporosis were grouped and categorized as abnormal BMD. Unconditional logistic regression analysis was used to estimate the odds ratios (OR of abnormal BMD values as measures of association, with 95% confidence intervals (CIs, adjusting for age, years since menopause, parity, and body mass index (BMI. RESULTS: The mean age of the women with and without breast cancer was 54.7 ± 5.8 years and 58.2 ± 4.8 years (p OBJETIVO: Comparar a densidade mineral óssea (DMO de mulheres na pós-menopausa com e sem câncer de mama. MÉTODOS: Conduziu-se estudo de corte transversal, incluindo 51 mulheres com câncer de mama e 71 mulheres sem câncer de mama, não usuárias de terapia hormonal, tamoxifeno ou de inibidores da aromatase. Avaliou-se a DMO, em T-score e em gramas por centímetro quadrado (g/cm², no colo do fêmur, trocânter, triângulo de Wards e na coluna lombar. Osteopenia e osteoporose foram agrupadas e categorizadas como DMO alterada. Utilizou-se a análise de regressão logística não condicional para estimar o odds ratios (OR de DMO alterada como medida de associação, com intervalo de confiança de 95% (IC 95%, ajustando-se por idade, anos de menopausa, paridade e índice de massa corpórea (IMC. RESULTADOS: A média de idade de mulheres com e sem câncer de mama foi 54,7 ± 5,8 anos e 58,2 ± 4,8 anos (p < 0,01, respectivamente. Após ajustar por idade, paridade e IMC, DMO alterada no colo do fêmur (OR ajustado: 4,8; IC 95%: 1,5-15,4, trocânter (OR
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SEM Characterization of an Irradiated Monolithic U-10Mo Fuel Plate
International Nuclear Information System (INIS)
Keiser, D.D. Jr.; Jue, J.F.; Robinson, A.B.
2010-01-01
Results of scanning electron microscopy (SEM) characterization of irradiated U-7Mo dispersion fuel plates with differing amounts of matrix Si have been reported. However, to date, no results of SEM analysis of irradiated U-Mo monolithic fuel plates have been reported. This paper describes the first SEM characterization results for an irradiated monolithic U-10Mo fuel plate. Two samples from this fuel plate were characterized. One sample was produced from the low-flux side of the fuel plate, and another was produced at the high-flux side of the fuel plate. This characterization focused on the microstructural features present at the U-10Mo foil/cladding interface, particularly the interaction zone that had developed during fabrication and irradiation. In addition, the microstructure of the foil itself was investigated, along with the morphology of the observed fission gas bubbles. It was observed that a Si-rich interaction layer was present at the U-10Mo foil/cladding interface that exhibited relatively good irradiation behavior, and within the U-10Mo foil the microstructural features differed in some respects from what is typically seen in the U-Mo powders of an irradiated dispersion fuel.
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DEFF Research Database (Denmark)
Zhou, Hong Wei; Mishnaevsky, Leon; Brøndsted, Povl
2010-01-01
Glass fiber-reinforced polymer (GFRP) composites are widely used in low-weight constructions. SEM (scanning electron microscopy) in situ experiments of damage growth in GFRP composite under three-point bending loads are carried out. By summarizing the experimental results of three groups of samples...
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International Nuclear Information System (INIS)
Costa de Almeida, Glauce Regina; Molina, Gabriela Ferian; Meschiari, Cesar Arruda; Barbosa de Sousa, Frederico; Gerlach, Raquel Fernanda
2009-01-01
The aims of this study were 1) to verify how close to the theoretically presumed areas are the areas of enamel microbiopsies carried out in vivo or in exfoliated teeth; 2) to test whether the etching solution penetrates beyond the tape borders; 3) to test whether the etching solution demineralizes the enamel in depth. 24 shed upper primary central incisors were randomly divided into two groups: the Rehydrated Teeth Group and the Dry Teeth Group. An enamel microbiopsy was performed, and the enamel microbiopsies were then analyzed by Scanning Electron Microscopy (SEM) and Polarizing Microscopy (PM). Quantitative birefringence measurements were performed. The 'true' etched area was determined by measuring the etched enamel using the NIH Image analysis program. Enamel birefringence was compared using the paired t test. There was a statistically significant difference when the etched areas in the Rehydrated teeth were compared with those of the Dry teeth (p = 0.04). The etched areas varied from - 11.6% to 73.5% of the presumed area in the Rehydrated teeth, and from 6.6% to 61.3% in the Dry teeth. The mean percentage of variation in each group could be used as a correction factor for the etched area. Analysis of PM pictures shows no evidence of in-depth enamel demineralization by the etching solution. No statistically significant differences in enamel birefringence were observed between values underneath and outside the microbiopsy area in the same tooth, showing that no mineral loss occurred below the enamel superficial layer. Our data showed no evidence of in-depth enamel demineralization by the etching solution used in the enamel microbiopsy proposed for primary enamel. This study also showed a variation in the measured diameter of the enamel microbiopsy in nineteen teeth out of twenty four, indicating that in most cases the etching solution penetrated beyond the tape borders.
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Directory of Open Access Journals (Sweden)
Rodrigo dos Santos Godoi
2009-07-01
Full Text Available O objetivo do trabalho foi determinar o crescimento, a produção e a qualidade das frutas do morangueiro cultivado em três sistemas fechados sem solo e com dois substratos. Os sistemas foram testados no interior de um abrigo telado, no Departamento de Fitotecnia da UFSM, no período entre 27 de abril e 21 de novembro de 2006. Esses sistemas foram constituídos por sacolas fertirrigadas por tubos gotejadores e calhas e leito de cultivo fertirrigados por subirrigação. Foram empregados substrato orgânico Plantmax PXT® e areia. O delineamento experimental utilizado foi um fatorial 3 x 2, com quatro repetições. A fertirrigação foi feita com solução nutritiva completa, sem nenhum descarte durante todo o período experimental, e as frutas foram colhidas maduras. Foram determinados os seguintes parâmetros: a produção, a firmeza, a acidez e o teor de sólidos solúveis totais. Interações significativas entre os sistemas e os substratos foram observadas. Na areia, destacou-se o cultivo nas calhas, com produção de 1017,4g planta-1, sendo 8,13% e 8,33% superior às sacolas e ao leito de cultivo, respectivamente. A produção mais elevada foi de 1196,5g planta-1, obtida com substrato orgânico no leito de cultivo, superior às sacolas em 10,9% e às calhas em 29,33%. Concluiu-se que o cultivo sem solo do morangueiro sem descartes de solução nutritiva é possível e que a produção é influenciada pelo sistema de cultivo e pelo substrato, sem efeitos sobre a qualidade das frutas.The objective of the research was to determine fruit production and quality of strawberry plants grown in three different closed soilless systems and two substrates. The experiment was conducted in a screenhouse at Department of Fitotecnia, UFSM, from April to November, 2006. The soilless growing systems were plastic bags, plastic troughs and growing beds, and the substrates were sand and the organic substrate Plantmax PXT®. A 3 x 2 factorial experimental design
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International Nuclear Information System (INIS)
EL-AKHDAR, E.A.H.; OUDA, S.M
2008-01-01
As an alternative to chemical control or as a part of integrated pest management (IPM program), there is a resurgence of interest in using microbial agents for pest population suppression before the application of the sterile insect technique (SIT) against the Mediterranean fruit fly, Ceratitis capitata (Wiedmann). The insect-fungus interaction between the fungal isolates, Aspergillus niger and Penicillium oxalicum, when applied as a spore suspension against the adults of Medfly in the laboratory showed visual fungal development after 7 days from inoculation. Examination of the infected parts of the dead fly with light microscopy showed a markedly damage as evidenced by the occurrence of the attached conidia and features of pathogen penetration. Using the scanning electron microscopy (SEM), the abundant sporulation of both fungal isolates was investigated over all parts of the dead fly and their associated sensillae. The recognized shape of the fungal conidial spores and their arrangement on the hyphae of both bio agents was investigated. This ultra structural study may be helpful in evaluating the effectiveness of both fungal bio agents on the functions of all infected parts of the insect and their associated sensillae (the main communication system between insects, their internal and external environment) and their main role in the courtship, male mating ability, the selection of fruit host plants necessary for the adults food and also the selection of a suitable oviposition site
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Ser(mos) com e sem cancro we-ness no casal
Santos, Inês Jorge
2016-01-01
Dissertação de Mestrado apresentada no ISPA – Instituto Universitário para obtenção do grau de Mestre em Psicologia especialidade de Psicologia Clínica. O objetivo desde estudo é compreender se o “We-ness” aumenta quando se verifica a presença da doença oncológica numa tónica de comparação de casais com cancro e casais sem cancro e verificar a perceção que os casais têm face ao “We-ness” e ao significado deste sentimento. A evidência de estudos ao nível do individuo, como memb...
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Macromolecular 3D SEM reconstruction strategies: Signal to noise ratio and resolution
International Nuclear Information System (INIS)
Woodward, J.D.; Wepf, R.A.
2014-01-01
Three-dimensional scanning electron microscopy generates quantitative volumetric structural data from SEM images of macromolecules. This technique provides a quick and easy way to define the quaternary structure and handedness of protein complexes. Here, we apply a variety of preparation and imaging methods to filamentous actin in order to explore the relationship between resolution, signal-to-noise ratio, structural preservation and dataset size. This information can be used to define successful imaging strategies for different applications. - Highlights: • F-actin SEM datasets were collected using 8 different preparation/ imaging techniques. • Datasets were reconstructed by back projection and compared/analyzed • 3DSEM actin reconstructions can be produced with <100 views of the asymmetric unit. • Negatively stained macromolecules can be reconstructed by 3DSEM to ∼3 nm resolution
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Dopant profiling based on scanning electron and helium ion microscopy
Energy Technology Data Exchange (ETDEWEB)
Chee, Augustus K.W., E-mail: kwac2@cam.ac.uk [Centre for Advanced Photonics and Electronics, Electrical Engineering Division, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA (United Kingdom); Boden, Stuart A. [University of Southampton, Electronics and Computer Science, Highfield, Southampton SO17 1BJ (United Kingdom)
2016-02-15
In this paper, we evaluate and compare doping contrast generated inside the scanning electron microscope (SEM) and scanning helium ion microscope (SHIM). Specialised energy-filtering techniques are often required to produce strong doping contrast to map donor distributions using the secondary electron (SE) signal in the SEM. However, strong doping contrast can be obtained from n-type regions in the SHIM, even without energy-filtering. This SHIM technique is more sensitive than the SEM to donor density changes above its sensitivity threshold, i.e. of the order of 10{sup 16} or 10{sup 17} donors cm{sup −3} respectively on specimens with or without a p–n junction; its sensitivity limit is well above 2×10{sup 17} acceptors cm{sup −3} on specimens with or without a p–n junction. Good correlation is found between the widths and slopes of experimentally measured doping contrast profiles of thin p-layers and the calculated widths and slopes of the potential energy distributions across these layers, at a depth of 1 to 3 nm and 5 to 10 nm below the surface in the SHIM and the SEM respectively. This is consistent with the mean escape depth of SEs in silicon being about 1.8 nm and 7 nm in the SHIM and SEM respectively, and we conclude that short escape depth, low energy SE signals are most suitable for donor profiling. - Highlights: • Strong doping contrast from n-type regions in the SHIM without energy-filtering. • Sensitivity limits are established of the SHIM and SEM techniques. • We discuss the impact of SHIM imaging conditions on quantitative dopant profiling. • Doping contrast stems from different surface layer thicknesses in the SHIM and SEM.
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Analysis of microtraces in invasive traumas using SEM/EDS.
Vermeij, E J; Zoon, P D; Chang, S B C G; Keereweer, I; Pieterman, R; Gerretsen, R R R
2012-01-10
Scanning electron microscopy in combination with energy-dispersive X-ray spectrometry (SEM/EDS) is a proven forensic tool and has been used to analyze several kinds of trace evidence. A forensic application of SEM/EDS is the examination of morphological characteristics of tool marks that tools and instruments leave on bone. The microtraces that are left behind by these tools and instruments on the bone are, however, often ignored or not noticed at all. In this paper we will describe the use of SEM/EDS for the analysis of microtraces in invasive sharp-force, blunt-force and bone-hacking traumas in bone. This research is part of a larger multi-disciplinary approach in which pathologists, forensic anthropologists, toolmark and microtrace experts work together to link observed injuries to a suspected weapon or, in case of an unknown weapon, to indicate a group of objects that could have been used as a weapon. Although there are a few difficulties one have to consider, the method itself is rather simple and straightforward to apply. A sample of dry and clean bone is placed into the SEM sample chamber and brightness and contrast are set such that bone appears grey, metal appears white and organic material appears black. The sample is then searched manually to find relevant features. Once features are found their elemental composition is measured by an energy dispersive X-ray spectrometer (EDS). This method is illustrated using several cases. It is shown that SEM/EDS analysis of microtraces in bone is a valuable tool to get clues about an unknown weapon and can associate a specific weapon with injuries on the basis of appearance and elemental composition. In particular the separate results from the various disciplines are complementary and may be combined to reach a conclusion with a stronger probative value. This is not only useful in the courtroom but above all in criminal investigations when one have to know for what weapon or object to look for. Copyright © 2011
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Directory of Open Access Journals (Sweden)
Leandro Souza da Silva
2003-06-01
Full Text Available O alagamento e a presença de plantas alteram as propriedades biológicas e químicas do solo em relação ao ambiente anteriormente oxidado, influenciando a disponibilidade de nutrientes. Foi conduzido um experimento com o objetivo de avaliar as alterações dos teores de alguns nutrientes na solução de um Planossolo e um Gleissolo durante o ciclo do arroz. Os solos foram acondicionados em vasos (50 litros contendo dispositivos para coleta da solução em diferentes profundidades, mantidos sem ou com plantas de arroz. A solução foi coletada aos 10, 19, 44, 77 e 113 dias de alagamento e determinados os teores de P, K, Ca, Mg, Fe e Mn. A concentração dos nutrientes na solução, especialmente o K, variou com a profundidade de coleta e com a presença de plantas, demonstrando a influência desses fatores na disponibilidade dos nutrientes em solos alagados.Flooding a soil and growing plant on it can change its biological and chemistry properties, in comparison with a non-flooded environment. An experiment was conducted in order to study the nutrients dynamics in the solution of two soils (Planossolo and Gleissolo during the rice cycle. Rice plants were cultivated in 50L containers having devices to collect soil solution at several depths (2.5, 5.0, 7.5 and 31cm. In the soil solution, with and without plant, P, K, Ca, Mg, Fe and Mn, were measured at 10, 19, 44, 77, and 113 days after the flooding. Potassium was especially sensible to the rice plant and depth of sampling
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Directory of Open Access Journals (Sweden)
Helena Alves Gouveia
2008-10-01
Full Text Available http://dx.doi.org/10.5007/1984-784x.2008v8n12p38 A serpente que engole a si mesma é uma figura curiosa do simbolismo de um processo de contínua transformação, de um movimento circular incessante, rumo à infinitude, sem traços de fim ou começo. Oroboro é um nome de origem grega que remete a esta serpente que se morde e penetra em si mesma ao engolir o próprio rabo. Mas também é o nome da revista de cultura editada em Curitiba pelos artistas-editores Ricardo Corona e Eliana Borges.
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Potenciais evocados auditivos de músicos com e sem ouvido absoluto
Oliveira, Letícia Ribeiro de
2014-01-01
Orientador: Prof. Dr. Francisco José Fraga da Silva Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia da Informação, 2014. Entende-se por ouvido absoluto a capacidade de produzir e/ou identificar e dar nome à frequência de qualquer nota musical sem a necessidade de uma referência externa. O estudo do ouvido absoluto pode ser uma oportunidade única para se investigar as interações entre informações linguísticas e não-linguísticas na memória de ...
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Directory of Open Access Journals (Sweden)
Damiana Cleuma de Medeiros
2008-06-01
Full Text Available Avaliou-se a qualidade de mudas de alface em função de substratos com e sem biofertilizante (aplicado aos 6; 12 e 18 dias após germinação em condições de casa-de-vegetação. O experimento foi conduzido em esquema fatorial inteiramente casualizado: 3 cultivares (Babá-de-Verão, Grand Rapids e Grandes Lagos x 3 tipos de substratos (areia lavada, composto orgânico e substrato comercial Plantmax® x 2 (com e sem biofertilizante, com quatro repetições. A avaliação foi feita aos 24 dias da germinação através de número de folhas, altura da parte aérea, comprimento da raiz, massa seca da parte aérea e massa seca da raiz. Houve efeito isolado dos fatores cultivares e substratos para número de folhas e comprimento da raiz. Houve efeito de interação cultivares x substratos para altura da parte aérea, massa seca da parte aérea e massa seca da raiz. Dentre as variáveis analisadas a cultivar Grand Rapids e o substrato composto orgânico foi a que obteve melhor resultado. Não houve influência significativa da aplicação de biofertilizante.The quality of lettuce seedlings depending on substrates and biofertilizer addition (at 6; 12 and 18 days after germination, under greenhouse conditions was evaluated. The experiment was carried out in a completely randomized factorial scheme: 3 cultivars (Babá-de-Verão, Grand Rapids and Great Lakes x 3 substrates (washed sand, organic compost and commercial substrate Plantmax® x 2 (with and without biofertilizer addition, with four replications. The evaluation was done on 24-day old seedlings through number of leaves, shoot height, root length, shoot dry mass and root dry mass. There was an isolated effect for cultivars and substrates with regard to the number of leaves and root length. There was cultivars x substrates interaction effect for shoot height, shoot dry mass and root dry mass. The best result was obtained with cultivar Grands Rapids grown in organic compost. There were no
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Contrast of Backscattered Electron SEM Images of Nanoparticles on Substrates with Complex Structure.
Kowoll, Thomas; Müller, Erich; Fritsch-Decker, Susanne; Hettler, Simon; Störmer, Heike; Weiss, Carsten; Gerthsen, Dagmar
2017-01-01
This study is concerned with backscattered electron scanning electron microscopy (BSE SEM) contrast of complex nanoscaled samples which consist of SiO 2 nanoparticles (NPs) deposited on indium-tin-oxide covered bulk SiO 2 and glassy carbon substrates. BSE SEM contrast of NPs is studied as function of the primary electron energy and working distance. Contrast inversions are observed which prevent intuitive interpretation of NP contrast in terms of material contrast. Experimental data is quantitatively compared with Monte-Carlo- (MC-) simulations. Quantitative agreement between experimental data and MC-simulations is obtained if the transmission characteristics of the annular semiconductor detector are taken into account. MC-simulations facilitate the understanding of NP contrast inversions and are helpful to derive conditions for optimum material and topography contrast.
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Enfermagem em cardiologia baseada em evidência
Directory of Open Access Journals (Sweden)
Eneida Rejane Rabelo da Silva
2007-10-01
Full Text Available Neste artigo apresentamos, dentro do cenário cardiovascular, estudos recentes do nosso grupo. Buscando melhores evidências de enfermagem investigamos por meio de ensaios clínicos randomizados (ECR estratégias de educação e acompanhamento destes pacientes (pctes. O primeiro ECR avaliou o impacto da educação individual e da orientação em grupo no conhecimento sobre doença e autocuidado em pctes com insuficiência cardíaca (IC. No grupo intervenção, houve uma melhora do conhecimento dos cuidados essenciais (controle de sal e da ingesta hídrica, peso diário, realização de atividade física P=0,008, demonstrando que o atendimento em grupo é semelhante ao individual. No ambiente hospitalar, segundo ECR, comparamos o efeito da educação de enfermagem e seguimento telefônico após alta versus educação sem a monitorização por telefone. Demonstramos que intervenção educativa durante a internação melhora o conhecimento da doença, autocuidado e qualidade de vida (P
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Cálculo de velocidades em acidentes de trânsito: Um software para investigação em física forense
Gurgel, W.P.; Gomes, L.M.; Ferreira, F.C.L.; Gester, R.M.
2015-01-01
Neste trabalho apresentamos e validamos o software Speed Calculations for Traffic Accidents (SCTA). Este aplicativo é voltado para a perícia forense e segue um protocolo que possibilita ao perito criminal, mesmo aquele sem formação em física, estimar as velocidades de veículos envolvidos em colisões e atropelamentos no trânsito. SCTA utiliza conceitos básicos de mecânica clássica, considera diferentes coeficientes de atrito e leva em conta as avarias e as características dos veículos envolvid...
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Neděla, Vilém; Hřib, Jiří; Havel, Ladislav; Hudec, Jiří; Runštuk, Jiří
2016-05-01
This article describes the surface structure of Norway spruce early somatic embryos (ESEs) as a typical culture with asynchronous development. The microstructure of extracellular matrix covering ESEs were observed using the environmental scanning electron microscope as a primary tool and using the scanning electron microscope with cryo attachment and laser electron microscope as a complementary tool allowing our results to be proven independently. The fresh samples were observed in conditions of the air environment of the environmental scanning electron microscope (ESEM) with the pressure from 550Pa to 690Pa and the low temperature of the sample from -18°C to -22°C. The samples were studied using two different types of detector to allow studying either the thin surface structure or material composition. The scanning electron microscope with cryo attachment was used for imaging frozen extracellular matrix microstructure with higher resolution. The combination of both electron microscopy methods was suitable for observation of "native" plant samples, allowing correct evaluation of our results, free of error and artifacts. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Directory of Open Access Journals (Sweden)
Brendow de Oliveira Fraga
2015-08-01
Full Text Available O objetivo deste artigo é analisar os elementos considerados relevantes pelo governo municipal no processo de planejamento público de um roteiro turístico no contexto da criatividade de uma cidade sem tradição na organização do setor. Para tanto, foram realizadas pesquisas documentais, entrevista no departamento de turismo da cidade em estudo e observações de campo nos atrativos do roteiro turístico. Como principal resultado observou-se no município estudado, a gestão pública do turismo tem se empenhado em integrar os pontos desenvolvimento da atividade turística, sobretudo por meio da reunião de organizações que possuem produtos (potencialmente criativos, apesar da roteirização apresentar problemas de implementação. Conclui-se que por meio da roteirização e da gestão que vem sendo empregada no município em análise, a realidade social tem sido transformada, e a gestão pública do turismo tem buscado sistematizar suas práticas no setor, mas ainda de forma pouco profissionalizada. Palavras-chave: Economia Criativa. Políticas Públicas de Turismo. Roteirização. Destino Turístico. Desenvolvimento Local.
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Bushong, Eric A.; Johnson, Donald D.; Kim, Keun-Young; Terada, Masako; Hatori, Megumi; Peltier, Steven T.; Panda, Satchidananda; Merkle, Arno; Ellisman, Mark H.
2014-01-01
The recently developed three-dimensional electron microscopic (EM) method of serial block-face scanning electron microscopy (SBEM) has rapidly established itself as a powerful imaging approach. Volume EM imaging with this scanning electron microscopy (SEM) method requires intense staining of biological specimens with heavy metals to allow sufficient back-scatter electron signal and also to render specimens sufficiently conductive to control charging artifacts. These more extreme heavy metal s...
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Ganho de força e função em idosos por treino isométrico com e sem resposta visual
Directory of Open Access Journals (Sweden)
Mauricio Ferraz de Arruda
2014-07-01
Full Text Available INTRODUÇÃO: A remediação das alterações fisiológicas que sofrem os idosos é um problema com o qual a saúde pública se defronta com frequência. A premência deste trabalho está em minimizar essa remediação e as alterações que ela propicia no âmbito músculo-esquelético, por meio de um trabalho físico condicionante, que busca aumentar a qualidade de vida dessa população. OBJETIVO: Avaliar o efeito do treinamento físico sob duas ópticas de comando terapêutico, com e sem resposta visual por unidade de pressão, bem como seus possíveis benefícios quanto ao ganho de torque muscular, inerente à funcionalidade citada no questionário de qualidade de vida SF-36, avaliando assim a influência do treinamento físico. MÉTODOS: A avaliação foi realizada por meio de um questionário de qualidade de vida SF-36 e do teste de levantar e sentar, além da aferição da força por meio do esfigmomanômetro modificado (EM. O individuo foi submetido a duas sessões semanais de exercícios durante um mês, com o protocolo de treinamento que constou de três séries de 10 repetições na cadeira flexora e extensora para ambos os joelhos de maneira isométrica. Os dados foram estatisticamente analisados pela análise de variância e desvio padrão (p < 0,05 e correlação de Pearson (p < 0,05. RESULTADOS: Notou-se melhora no quadro geral dos idosos, sendo que houve aumento estatisticamente significante no estado geral de saúde, redução da limitação por aspectos físicos, redução da dor e no aumento da capacidade funcional, bem como um incremento da força de flexão e extensão, que teve reflexo positivo no teste funcional. CONCLUSÃO: Houve correlação extremamente válida entre o ganho de força em flexão com o teste de sentar e levantar, com o qual, apesar de ganho menor comparado ao ganho de força em extensão, estabeleceu-se correlação com o ganho funcional, independentemente da resposta visual ao exercício.
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STEM mode in the SEM for the analysis of cellular sections prepared by ultramicrotome sectioning
International Nuclear Information System (INIS)
Hondow, N; Harrington, J; Brydson, R; Brown, A
2012-01-01
The use of the dual imaging capabilities of a scanning electron microscope fitted with a transmitted electron detector is highlighted in the analysis of samples with importance in the field of nanotoxicology. Cellular uptake of nanomaterials is often examined by transmission electron microscopy of thin sections prepared by ultramicrotome sectioning. Examination by SEM allows for the detection of artefacts caused by sample preparation (eg. nanomaterial pull-out) and the complementary STEM mode permits study of the interaction between nanomaterials and cells. Thin sections of two nanomaterials of importance in nanotoxicology (cadmium selenide quantum dots and single walled carbon nanotubes) are examined using STEM mode in the SEM.
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Assessment of engineered surfaces roughness by high-resolution 3D SEM photogrammetry
Energy Technology Data Exchange (ETDEWEB)
Gontard, L.C., E-mail: lionelcg@gmail.com [Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica, Universidad de Cádiz, Puerto Real 11510 (Spain); López-Castro, J.D.; González-Rovira, L. [Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica, Escuela Superior de Ingeniería, Laboratorio de Corrosión, Universidad de Cádiz, Puerto Real 11519 (Spain); Vázquez-Martínez, J.M. [Departamento de Ingeniería Mecánica y Diseño Industrial, Escuela Superior de Ingeniería, Universidad de Cádiz, Puerto Real 11519 (Spain); Varela-Feria, F.M. [Servicio de Microscopía Centro de Investigación, Tecnología e Innovación (CITIUS), Universidad de Sevilla, Av. Reina Mercedes 4b, 41012 Sevilla (Spain); Marcos, M. [Departamento de Ingeniería Mecánica y Diseño Industrial, Escuela Superior de Ingeniería, Universidad de Cádiz, Puerto Real 11519 (Spain); and others
2017-06-15
Highlights: • We describe a method to acquire a high-angle tilt series of SEM images that is symmetrical respect to the zero tilt of the sample stage. The method can be applied in any SEM microscope. • Using the method, high-resolution 3D SEM photogrammetry can be applied on planar surfaces. • 3D models of three surfaces patterned with grooves are reconstructed with high resolution using multi-view freeware photogrammetry software as described in LC Gontard et al. Ultramicroscopy, 2016. • From the 3D models roughness parameters are measured • 3D SEM high-resolution photogrammetry is compared with two conventional methods used for roughness characetrization: stereophotogrammetry and contact profilometry. • It provides three-dimensional information with high-resolution that is out of reach for any other metrological technique. - Abstract: We describe a methodology to obtain three-dimensional models of engineered surfaces using scanning electron microscopy and multi-view photogrammetry (3DSEM). For the reconstruction of the 3D models of the surfaces we used freeware available in the cloud. The method was applied to study the surface roughness of metallic samples patterned with parallel grooves by means of laser. The results are compared with measurements obtained using stylus profilometry (PR) and SEM stereo-photogrammetry (SP). The application of 3DSEM is more time demanding than PR or SP, but it provides a more accurate representation of the surfaces. The results obtained with the three techniques are compared by investigating the influence of sampling step on roughness parameters.
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Are the evidences of forensic entomology preserved in ethanol suitable for SEM studies?
López-Esclapez, Raquel; García, María-Dolores; Arnaldos, María-Isabel; Presa, Juan José; Ubero-Pascal, Nicolás
2014-07-01
In forensic practice, the use of arthropod evidences to estimate the postmortem interval is a very good approach when the elapsed time from death is long, but it requires the correct identification of the specimens. This is a crucial step, not always easy to achieve, in particular when dealing with immature specimens. In this case, scanning electronic microscopy (SEM) can be useful, but the techniques used to preserve specimens in forensic practice are usually different from those used to prepare specimens for SEM studies. To determine whether forensic evidences preserving techniques are also compatible with SEM analysis, we have compared specimens of all the immature stages of Calliphora vicina Robineau-Desvoidy, 1830 (Diptera, Calliphoridae) preserved in 70% ethanol, with others prepared with aldehydic fixative techniques that are more appropriate for SEM studies. At the same time, two drying techniques have also been compared with both fixative techniques, the critical point drying and air-drying following with hexamethyldisilizane treatment (HMDS). Our results indicate that there are not basis against recommending the use of ethanol to preserve forensic entomological evidences and that both drying methods appear to offer good results for second and third instar larvae, although HMDS behaves better with eggs and pupae. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Directory of Open Access Journals (Sweden)
José Celso Ardengh
2010-01-01
colecistomicrolitíase (cálculos com até 3 mm. Não há, no momento, consenso quanto ao melhor método propedêutico para diagnosticá-lo e, entre os propostos, nenhum apresenta alta sensibilidade. A ecoendoscopia (EE é excelente no diagnóstico da pancreatite crônica incipiente e microcálculos da vesícula biliar (MCV ou colédoco. São poucas as referências na literatura internacional e nenhuma na nacional a respeito do emprego da EE na PA. O objetivo deste trabalho é o de estabelecer o valor da EE no diagnóstico da colecistomicrolitíase em doentes com PA sem causa aparente. MÉTODOS: Trinta e seis pacientes com o diagnóstico de PA sem causa aparente foram consecutivamente estudados durante cinco anos. Dos enviados para exame ecoendoscópico, 21 mulheres e 15 homens com média de idade de 41,6 anos. Todos haviam sido submetidos antes a pelo menos um US e uma TC, que não revelaram alterações na via bílio-pancreática e 63,9% deles tinham apresentado mais de um episódio de PA. O diagnóstico da colecistomicrolitíase pela EE realizada até uma semana durante o surto de PA baseou-se no tamanho do cálculo (até 3 mm, inclusive e hiperecogeneicidade com ou sem sombra acústica. Todos os doentes foram colecistectomizados, após o exame ecoendoscópico. RESULTADO: O exame das peças cirúrgicas mostrou que 27 (75% doentes apresentavam MCV e nove (25% não. A EE levou a erro no diagnóstico da microlitíase em seis (16,8% casos, quatro casos de falsos-positivos e dois casos de falsos-negativos. Em 30 casos (83,2% houve confirmação dos seus resultados. A sensibilidade, a especificidade, os valores preditivos positivo, negativo e a acurácia (com intervalo de confiança de 95% para a EE no diagnóstico dos MCV foram: 92,6% (74,2 a 98,7%, 55,6% (22,7 a 84,7%, 86,2% (67,4% a 95,5%, 71,4% (30,3 a 94,9% e 83,2% (66,5% a 93% respectivamente. CONCLUSÃO: A EE mostra-se, portanto, de grande valor na identificação da colecistomicrolitíase e a PA não deve ser considerada sem
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Scanning electron microscopy-energy dispersive X-ray spectrometer ...
African Journals Online (AJOL)
The distribution of arsenic (As) and cadmium (Cd) in himematsutake was analyzed using scanning electron microscopy-energy dispersive X-ray spectrometer (SEM-EDX). The atomic percentage of the metals was confirmed by inductively coupled plasma-mass spectrometer (ICP-MS). Results show that the accumulation of ...
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Directory of Open Access Journals (Sweden)
Emídio Valenti Tavares
1999-08-01
Full Text Available O principal objetivo deste estudo foi verificar as possíveis alterações de acuidade visual e pressão intra-ocular em jogadores de futebol. A clínica Oftalmos e Cirurgia Oftalmológica submeteu à avaliação oftalmológica 127 atletas futebolistas provenientes de várias categorias, incluindo mulheres, com idades variando de 14 a 33 anos. Todos foram submetidos a testes de acuidade visual sem correção, utilizando-se a tabela de Snellen e avaliando-se a pressão intra-ocular de não contato com um tonômetro computadorizado (modelo TX-10, Canon, EUA. Além disso, os atletas foram submetidos a exame de auto-refração, no equipamento auto-refrator (modelo R-30, Canon, EUA. Os seguintes parâmetros utilizados e os resultados encontrados foram: dos 127 atletas avaliados, 56 (44% apresentaram alterações de auto-refração, consideradas de grau mais ou menos importante em um ou ambos os olhos. No teste de acuidade visual, 3% e 2,4% dos atletas apresentaram, no OD e OE, somente 20/100 e 20/200 pés de visão, respectivamente. Em uma jogadora, foi constatada catarata puntata congênita. Os resultados da tonometria mostraram, em 5 atletas de cor negra, quadro suspeito de glaucoma (necessitando investigação mais apurada.Concluindo, o estudo comprovou a importância da oftalmologia como medida preventiva e/ou corretiva na identificação de possíveis alterações oftalmológicas em atletas futebolistas, devendo ser uma prática rotineira nesse esporte.
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Prolongamentos na fala de adultos com e sem gagueira
Directory of Open Access Journals (Sweden)
Pâmila Bento da Silva
Full Text Available RESUMO Objetivo: realizar uma análise quantitativa e qualitativa dos prolongamentos de adultos com e sem gagueira. Métodos: os participantes foram divididos em: Grupo de Pesquisa (GP, 15 adultos com gagueira e Grupo Controle (GC, 15 fluentes. Os procedimentos utilizados foram: avaliação da fluência, Instrumento de Gravidade da Gagueira e análises quantitativa e qualitativa dos prolongamentos. Resultados: GP mostrou maior número de prolongamentos não hesitativos, enquanto que GC mostrou maior ocorrência de prolongamentos hesitativos em relação ao total das disfluências. Prolongamentos não hesitativos ocorreram com maior frequência na palavra inicial e monossilábica, bem como na posição medial da frase para GP. Em relação à tensão muscular e duração, observou-se diferença apenas para a tensão muscular nos prolongamentos não hesitativos com maior média de ocorrência para GP. Conclusão: os prolongamentos não hesitativos ocorreram com maior frequência no GP, nas palavras iniciais, monossílabos e na posição medial da frase. Qualitativamente a tensão muscular foi uma característica típica dos prolongamentos não hesitativos no GP. Com relação aos prolongamentos hesitativos houve semelhança entre os adultos dos dois grupos quanto à frequência em relação ao total da fala, a posição dos prolongamentos nas palavras e nas frases e nos aspectos qualitativos, relacionados a tensão muscular e duração.
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Precisão da retinoscopia sem lentes neutralizadoras na hipermetropia experimental de olho artificial
Directory of Open Access Journals (Sweden)
Beatriz Simões-Corrêa
2012-10-01
Full Text Available OBJETIVO: Avaliar a acurácia e a precisão da retinoscopia sem lentes neutralizadoras na hipermetropia experimental de olho artificial. MÉTODOS: Observação da projeção da faixa do retinoscópio em olho artificial preparado para apresentar hipermetropias de +1,00 D a +8,00 D. A movimentação da faixa é feita simultaneamente com a variação da sua largura, deslocando a luva do retinoscópio até a obtenção da neutralização do movimento. O retinoscópio foi preparado para dois modos de medida: com escala milimétrica sob a luva e com acoplamento a potenciômetro ligado a multímetro de leitura digital em ohms (Ù. Oito médicos oftalmologistas realizaram 1200 retinoscopias em cada modo de medida, num total de 2400. Calculou-se a média e o desvio padrão das observações. Para comparar os resultados em mm e em ohms (Ù calculou-se o coeficiente de variação (CV a partir dos desvios padrão das observações em cada modo. RESULTADOS: Pelos modos descritos foi possível estimar hipermetropias até +4,00 dioptrias. CONCLUSÃO: A acurácia e a reprodutibilidade experimentais foram boas na identificação de hipermetropias até +4 ,00 D.
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The use of SEM/EDS method in mineralogical analysis of ordinary chondritic meteorite
Directory of Open Access Journals (Sweden)
Breda Mirtič
2009-12-01
Full Text Available The aim of this study was to evaluate the potential of scanning electron microscopy coupled with energy dispersiveX-ray spectroscopy (SEM/EDS for determination of mineral phases according to their stoichiometry and assessment of mineral composition of ordinary chondritic meteorite. For the purposes of this study, H3 type ordinary chondritic meteorite Abbott was selected. SEM/EDS allows identification and characterisation of mineralphases, whose size is below the resolution of an optical microscope. Mineral phases in chondrules and interstitial matrix were located in backscattered electron (BSE mode and were assessed from atomic proportions of constituent elements, obtained by the EDS analysis. SEM/EDS analyses of mineral phases showed that Abbott meteorite is characterised by Fe-rich (Fe, Ni-alloy kamacite, Fe-sulphide troilite or pyrrhotite, chromite, Mg-rich olivine, orthopyroxene bronzite or hypersthene, clinopyroxene Al-diopside, acid plagioclase oligoclase, accessory mineral chlorapatite and secondary minerals Fe-hydroxides (goethite or lepidocrocite. Results of semi-quantitative analyses confirmed that most of analysed mineralphases conform well to stoichiometric minerals with minor deviations of oxygen from stoichiometric proportions. Comparison between mineral phases in chondrules and interstitial matrix was also performed, however it showed no significant differences in elemental composition.Differences in chemical composition between minerals in interstitial matrix and chondrules are sometimes too small to be discernedby the SEM/EDS, therefore knowledge of SEM/EDS capabilities is important for correct interpretation of chondrite formation.
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A semântica formal das línguas naturais: histórias e desafios
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José Borges Neto
2014-03-01
Full Text Available Este artigo faz um resumo da história dos estudos semânticos noBrasil e no mundo, sobretudo das transformações iniciadas nadécada de 1970 e da abertura para uma semântica formalautônoma, que, hoje em dia, comporta diferentes visões sobre arelação sintaxe e semântica, da centralidade da sintaxe aoisomorfismo sintaxe semântica. Mostramos como as ideias do lógicoRichard Montague impulsionaram, através de Barbara Partee eEmmon Bach entre outros, tais estudos, estimulando o surgimentode novas vertentes, e como essas novas tendências foram inseridasno Brasil pela Unicamp com a ajuda de pesquisadores comoMarcelo Dascal, Rodolfo Ilari e Carlos Franchi. O artigo iniciacom uma breve descrição do que é a semântica formal,diferenciando-a de outras semânticas e, principalmente, dasemântica lógica, praticada pelos filósofos, cujo objetivo é descreverraciocínios válidos. A semântica formal é uma ciência empíricaque busca explicar o conhecimento semântico que um falante tem– sua capacidade de relacionar linguagem a algo que não élinguagem (mundos, modelos, conceitos, a composicionalidade e relações sistemáticas entre sentenças – através de umametalinguagem lógico-matemática. Esse empreendimento temsido bem sucedido, se expandindo para além da semântica emdireção a uma maior interação com a pragmática formal. Astendências atuais são de interação com outras disciplinas – apsicolinguística, por exemplo – e a preocupação com línguas poucodescritas, como as línguas indígenas brasileiras. No Brasil, asemântica formal ganhou impulso com a criação dos workshops etem conseguido um espaço cada vez mais significativo na linguísticanacional e internacional.
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José Eisenberg
2000-05-01
Full Text Available O texto resenha Ao leitor sem medo, de Renato Janine Ribeiro (Belo Horizonte, UFMG, 1999.This text is a review of Ao leitor sem medo by Renato Janine Ribeiro (Belo Horizonte, UFMG, 1999
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Dos Santos, Q M; Avenant-Oldewage, A
2015-02-01
Classification of most monogeneans is primarily based on size, shape, and arrangement of haptoral sclerites. These structures are often obscured or misinterpreted when studied using light microscopy, leading to confusion regarding defining characters. Scanning electron microscopy (SEM) has predominantly been used to study haptoral sclerites in smaller monogeneans, focusing on hooks and anchors. In the Diplozoidae, SEM has not been used to study haptoral sclerites. Using new and modified techniques, the sclerites of diplozoids collected in South Africa were successfully studied using SEM. The digestion buffer from a DNA extraction kit was used to digest the surrounding tissue, and Poly-L-lysine-coated and concavity slides were employed to limit the movement and loss of sclerites, with the latter being more user-friendly. In addition to the success of visualizing the sclerites using SEM, the digested tissue from as little as half of the haptor provided viable genetic material for molecular characterization. From the results presented here, the study of the sclerites of larger monogeneans using SEM, including those bearing clamps, is a viable possibility for future research. Also, this method may be beneficial for the study of other, non-haptoral sclerites, such as cirri in other families of monogeneans. During this study, Labeo capensis was noted as a valid host of Paradiplozoon vaalense in a region of the Vaal River where the type host, Labeo umbratus, appears to be absent.
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Detection of glass particles on bone lesions using SEM-EDS.
Montoriol, Romain; Guilbeau-Frugier, Céline; Chantalat, Elodie; Roumiguié, Mathieu; Delisle, Marie-Bernadette; Payré, Bruno; Telmon, Norbert; Savall, Frédéric
2017-09-01
The problem of identifying the wounding agent in forensic cases is recurrent. Moreover, when several tools are involved, distinguishing the origin of lesions can be difficult. Scanning electron microscopy (SEM)/energy dispersive X-ray analysis (EDS) equipment is increasingly available to the scientific and medical community, and some studies have reported its use in forensic anthropology. However, at our knowledge, no study has reported the use of SEM-EDS in forensic cases involving glass tools, whether in case reports or experiments. We performed an experimental study on human rib fragments, on which we manually created wounds using fragments of window and mirror glass. SEM-EDS was executed on samples without any further preparation on low vacuum mode, then on the same samples after defleshing them completely by boiling them. Window and mirror glass particles were detected on experimental wounds. Both had silica in their spectra, and the opaque side of the mirror contained titanium, allowing for their identification. Boiling and defleshing the bone samples involved a loss of information in terms of the number of wounds detected as positive for glass particles and in the number of glass particles detected, for both window and mirror glass. We suggest the analysis of wounds with suspected glass particles using low vacuum mode and with no defleshment by boiling.
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Silvana Aparecida Borsetti Gregorio Vidotti
2009-12-01
Full Text Available A Ciência da Informação solicita definições e redefinições de métodos que valorizem e destaquem os aspectos importantes das relações de disseminação, de recuperação e de compartilhamento de conhecimentos quando ocorre a rearticulação das relações sociais e de produção em torno das Tecologias de Informação e Comunicação (TICs. Busca-se nas interdisciplinaridades e transdisciplinaridades investigar e dialogar com os diversos campos do conhecimento em rede. Apresenta-se o modelo-teoria de Sáez Vacas (2002 para definir e estudar o Novo Entorno Tecnosocial (N.E.T segundo uma perspectiva sistêmica da infra-estrutura digital extremamente complexa, a Rede Universal Digital (R.U.D. com instrumentos tecnológicos para usuários não técnicos. O momento atual oferece a possibilidade de construção de um saber colaborativo marcado pela inteligência coletiva, em ações sociais de transferência de informação, sob o olhar das redes sociais como um ambiente antropológico de possibilidades. Avanços sociais e tecnológicos criam uma nova dinâmica da Rede e define o aparecimento da Web 2.0, Web Social ou a Web NG (Nova Geração de usuários, os nativos digitais, Web Semântica e Web Social Semântica.
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Ítalo A. Sherlock
1976-02-01
Full Text Available Foi verificada a transmissão sucessiva do T. cruzi em três gerações da cobaia Cavia porcellus sem a participação de triatomíneos. Embora não fosse determinado qual das vias, se placentária, leite, excreções ou contágio direto pelo qual o protozoário foi transmitido para os descendentes, chama-se atenção para a importância da manutenção de reservatórios da Doença de Chagas, mesmo na ausência de vetores invertebrados.The sucessive transmission of Trypanosoma cruzi among three generations of the guinea pig Cavia porcellus without the participation of triatomine bugs is verified. Although the mode of transmission, such as congenital, infected milk or other excretion or direct contagion was not defined, this maybe of importance in natural maintenance of reservoirs of T. cruzi without the invertebrate vectors.
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Andrea Krystina Vinente Guimaraes
2010-12-01
Full Text Available Avaliou-se a composição botânica da dieta em pastagens de capim marandú (B. brizantha e capim quicuio (B. humidicola consorciadas com leguminosas, em dois métodos de preparo de área: com e sem queima. Foram testadas três pastagens para cada experimento: 1. QB - B. humidicola + B. brizantha cv. Marandu. 2. QBAL - B. humidicola + B. brizantha consorciada com A. pintoi cv. Amarilo + L. leucocephala cv. Cunninghan. 3. QBAC - B. humidicola + B. brizantha consorciada com A. pintoi cv. Amarilo + C. Argentea (Cratylia. A composição botânica foi determinada usando a técnica da análise microhistologica de fezes. As coletas de fezes foram realizadas a cada dezoito dias. O consumo de quicuio e de espécies da capoeira foram superiores na época seca e de braquiarão, na chuvosa. As percentagens de quicuio foram superiores no método com queima, as de braquiarão, no método mulch. As percentagens de braquiarão foram superiores nas pastagens de QB e QBAL e as de leguminosas, nas pastagens consorciadas com leguminosas. Foram encontradas 14 famílias e 23 espécies. O método de preparo de área infuenciou a composição botânica da dieta. As espécies da capoeira tiveram pequena participação na composição botânica da dieta dos animais.
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Real-time scanning charged-particle microscope image composition with correction of drift.
Cizmar, Petr; Vladár, András E; Postek, Michael T
2011-04-01
In this article, a new scanning electron microscopy (SEM) image composition technique is described, which can significantly reduce drift related image corruptions. Drift distortion commonly causes blur and distortions in the SEM images. Such corruption ordinarily appears when conventional image-acquisition methods, i.e., "slow scan" and "fast scan," are applied. The damage is often very significant; it may render images unusable for metrology applications, especially where subnanometer accuracy is required. The described correction technique works with a large number of quickly taken frames, which are properly aligned and then composed into a single image. Such image contains much less noise than the individual frames, while the blur and deformation is minimized. This technique also provides useful information about changes of the sample position in time, which may be applied to investigate the drift properties of the instrument without a need of additional equipment.
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Osmar Avanzi
2008-06-01
Full Text Available OBJETIVO: Comparar clínica e radiologicamente os resultados a longo prazo do tratamento conservador da fratura explosão toracolombar, em pacientes com e sem fratura do arco vertebral posterior, com o propósito de avaliar eventuais diferenças na evolução destes dois tipos de lesão. MÉTODOS: Foram avaliados, retrospectivamente, os prontuários e exames de imagem (radiografias e tomografias computadorizadas de 25 pacientes sem déficit neurológico, com fratura toracolombar tipo explosão tratados não cirurgicamente e comparados o grau de progressão da cifose entre os casos com fratura da lâmina (grupo 1 e sem fratura posterior (grupo 2. Desses, 13 pacientes foram submetidos à avaliação comparativa por meio da escala visual analógica de dor (VAS, da escala de dor e trabalho de Denis e do questionário de qualidade de vida SF-36. RESULTADOS: Foram analisados 25 pacientes (36% do grupo A e 74% do grupo B com tempo médio de seguimento de 111,64 meses. Não houve diferença em relação ao grau de progressão da cifose durante o seguimento entre os grupos A e B (5,22º x 4,63º - p = 0,650. Dos 13 pacientes analisados funcionalmente, 46% eram do grupo A e 54% do grupo B. Nesta avaliação, apesar da VAS pior (1,83 x 5,00 - p = 0,015 nos pacientes sem fratura posterior (grupo B, não houve diferença em relação à escala de Denis (4,00 x 5,71 - p > 0,05 e SF-36 (98,60 x 90,83 - p = 0,168 entre os dois grupos. CONCLUSÃO: A fratura do arco posterior, isoladamente, parece não ser indicativo de instabilidade ou de mau prognóstico nas fraturas toracolombares tipo explosão.OBJECTIVE: To make a clinical and radiological comparison of long term results of the conservative treatment of thoracolumbar burst fractures, in patients with and without fracture in the posterior vertebral arch, in order to assess possible differences in the evolution of the two types of lesion. METHODS: A retrospective analysis was made of the clinical records and
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SEM characterization of an irradiated monolithic U-10Mo fuel plate
International Nuclear Information System (INIS)
Keiser, D.D. Jr.; Jue, J.F.; Robinson, A.B.; Finlay, M.R.
2010-01-01
Results of scanning electron microscopy (SEM) characterization of irradiated U-7Mo dispersion fuel plates with differing amounts of matrix Si have been reported. However, to date, no results of SEM analysis of irradiated U-Mo monolithic fuel plates have been reported. This paper describes the first SEM characterization results for an irradiated monolithic U-10Mo fuel plate. Two samples from this fuel plate were characterized. One sample was produced from the low-flux side of the fuel plate, and another was produced at the high-flux side of the fuel plate. This characterization focused on the microstructural features present at the U-10Mo foil/AA6061 cladding interface, particularly the interaction zone that had developed during fabrication and any continued development during irradiation. In addition, the microstructure of the foil itself was investigated, along with the morphology of the observed fission gas bubbles. It was observed that a Si-rich interaction layer was present at the U-10Mo foil/cladding interface that exhibited relatively good irradiation behavior, and within the U-10Mo foil the microstructural features differed in some respects from what is typically seen in the U-7Mo powders of an irradiated dispersion fuel. (author)
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Linguagens documentárias e vocabulários semânticos para a web: elementos conceituais: resenha
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Eliana Maria dos Santos Bahia
2012-01-01
Full Text Available José Antônio Moreiro González, Professor catedrático de Biblioteconomia e Documentação da Universidad Carlos III de Madrid na Espanha, com experiência na técnica de análise de conteúdo documental e sobre questões conceituais da documentação. O autor trata das Linguagens Documentárias e Vocabulários Semânticos para a Web, que a Editora da Universidade Federal da Bahia apresenta aos leitores. O resultado é um texto com a potencialidade tanto de servir como introdução ao tema para o leitor não especialista como apresentar uma síntese ampla e atualizada dos principais problemas e avanços no estudo das linguagens documentárias e vocabulários semânticos para a web. O livro compõe-se de onze (11 capítulos, delineados pelo autor, descrevendo os elementos conceituais das linguagens documentárias e dos vocabulários semânticos para a web. O primeiro capítulo trata das Bases Epistemológicas da Representação da Informação: origem da representação conceitual, no qual apresenta a origem das relações entre conceitos; os conceitos principais e sua organização em macroestruturas. Análise da leitura dos documentos na pesquisa para obter a informação, o resumo do autor, título, sumários, tabelas, índices, ilustrações, legendas para recuperar a informação. No segundo capítulo (Para Melhor Entender a Recuperação Léxica da Informação, o Autor pontua o acesso contemporâneo à informação dos documentos, com os respectivos conceitos - da representação do na era sociedade do conhecimento. O terceiro capítulo (Requerimentos Fundamentais da Nova Web, compreende-se três seções: dimensões da web social e da web semântica; finalidade da chamada web semântica, e; possibilidades de evolução. O autor aponta as mudanças especificando a web 2.0 e sua evolução para a web semântica; a web 2.0 e a web semântica convirjam para web 3.0; e a web 2.0 e a web semântica coexistindo harmoniosamente no ciberespa
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Linguagens documentárias e vocabulários semânticos para a web: elementos conceituais: resenha
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Eliana Maria dos Santos Bahia
2012-08-01
Full Text Available http://dx.doi.org/10.5007/1518-2924.2012v17n34p193 José Antônio Moreiro González, Professor catedrático de Biblioteconomia e Documentação da Universidad Carlos III de Madrid na Espanha, com experiência na técnica de análise de conteúdo documental e sobre questões conceituais da documentação. O autor trata das Linguagens Documentárias e Vocabulários Semânticos para a Web, que a Editora da Universidade Federal da Bahia apresenta aos leitores. O resultado é um texto com a potencialidade tanto de servir como introdução ao tema para o leitor não especialista como apresentar uma síntese ampla e atualizada dos principais problemas e avanços no estudo das linguagens documentárias e vocabulários semânticos para a web. O livro compõe-se de onze (11 capítulos, delineados pelo autor, descrevendo os elementos conceituais das linguagens documentárias e dos vocabulários semânticos para a web. O primeiro capítulo trata das Bases Epistemológicas da Representação da Informação: origem da representação conceitual, no qual apresenta a origem das relações entre conceitos; os conceitos principais e sua organização em macroestruturas. Análise da leitura dos documentos na pesquisa para obter a informação, o resumo do autor, título, sumários, tabelas, índices, ilustrações, legendas para recuperar a informação. No segundo capítulo (Para Melhor Entender a Recuperação Léxica da Informação, o Autor pontua o acesso contemporâneo à informação dos documentos, com os respectivos conceitos - da representação do na era sociedade do conhecimento. O terceiro capítulo (Requerimentos Fundamentais da Nova Web, compreende-se três seções: dimensões da web social e da web semântica; finalidade da chamada web semântica, e; possibilidades de evolução. O autor aponta as mudanças especificando a web 2.0 e sua evolução para a web semântica; a web 2.0 e a web semântica convirjam para web 3.0; e a web 2.0 e a web
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Picoloto, Luana Altran; Cardoso, Ana Cláudia Vieira; Cerqueira, Amanda Venuti; Oliveira, Cristiane Moço Canhetti de
2017-01-01
RESUMO Objetivo Verificar o efeito da retroalimentação auditiva atrasada na fluência da fala de indivíduos que gaguejam, com e sem alteração do processamento auditivo central. Método Participaram 20 indivíduos com gagueira, de sete a 17 anos, divididos em dois grupos, cada um com 10 indivíduos: Grupo Gagueira com Transtorno do Processamento Auditivo (GGTPA) e Grupo Gagueira (GG) sem alteração de processamento auditivo central. Os procedimentos foram: avaliação da fluência com retroalimentaç...
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Simone Aparecida Capellini
2009-01-01
Full Text Available OBJETIVOS: caracterizar e comparar o desempenho de escolares com e sem dificuldades de aprendizagem no ensino particular em habilidades fonológicas, nomeação rápida, leitura e escrita. MÉTODOS: participaram desse estudo 60 escolares de 2ª a 4ª séries de escola de ensino particular, distribuídos em 6 grupos, sendo cada grupo composto por 10 escolares, sendo 3 grupos de escolares com dificuldades de aprendizagem e 3 grupos de escolares sem dificuldades de aprendizagem. Como procedimentos, foram realizadas a prova de nomeação automática rápida, a de consciência fonológica e a prova de leitura oral e escrita sob ditado. RESULTADOS: os resultados desse estudo evidenciaram desempenho superior dos escolares sem dificuldades de aprendizagem em relação àqueles com dificuldades. Os escolares com dificuldades de aprendizagem apresentaram maior relação velocidade/tempo em tarefas de nomeação e, conseqüentemente, desempenho inferior em tarefas de consciência fonológica e leitura e escrita de palavras isoladas quando comparados aos sem dificuldades de aprendizagem. CONCLUSÃO: os escolares com dificuldades de aprendizagem apresentaram comprometimento na relação entre as capacidades de nomeação e automatização dos estímulos apresentados com a capacidade de acesso lexical, discriminação visual, freqüência de uso dos estímulos e competição para a apresentação do menor tempo possível na nomeação dos códigos necessários para o estabelecimento do mecanismo de conversão fonema-grafema, exigido para a realização da leitura e escrita em um sistema alfabético como o português.PURPOSE: characterizing and comparing the performance of students with and without learning difficulties from the private education in phonological awareness, rapid naming, reading and writing. METHODS: sixty private students from 2nd to 4th grade participated, distributed into 6 groups - each one was composed of 10 students being 3 groups of
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C.G. Valadares
2016-06-01
Full Text Available RESUMO O objetivo deste trabalho foi avaliar o valor nutricional e determinar a energia metabolizável do farelo residual de milho (FRM sem e com o uso da enzima alfa- amilase. Foi realizado um experimento de metabolismo com 180 pintos machos Cobb com 14 dias, distribuídos em um delineamento inteiramente ao acaso, com seis tratamentos, cinco repetições e seis aves por parcela. As dietas experimentais foram: T1: ração referência (RR, T2: 60% T1 + 40% de FRM, T3: RR + enzima, T4: 60% T1 + 40% de FRM com adição de enzima, T5: RR com substituição de 100% do milho pelo FRM e T6: RR com substituição de 100% do milho pelo FRM com adição de enzima. A composição química do FRM foi: 88,33% de matéria seca (MS, 10,23% de proteína bruta (PB, 15,44% de extrato etéreo (EE, 4,33% de cinzas (CZ e 4555kcal/kg de energia bruta (EB. Os valores dos coeficientes de metabolizabilidade aparente para o FRM sem e com adição de enzima foram, respectivamente, de 73,37% e 76,33% para MS (p=0,0136, 70,44% e 70,39% para PB (p=0,9595 e de 74,79% e 76,77% para EB (p=0,0128. Os valores da energia metabolizável aparente (EMA e da EMA corrigida para retenção de nitrogênio (EMAn para o FRM (na base natural foram de 3322±19 e 3241±18kcal/kg e de 3334±16 e 3261±17kcal/kg, respectivamente, sem e com adição de enzima. A adição da enzima não teve efeito estatístico significativo sobre os valores de EMA e EMAn, entretanto houve efeito positivo no coeficiente de metabolização da energia.
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Flávia Coelho de Souza Botter
Full Text Available OBJETIVO: Estudar as alterações hemodinâmicas e respiratórias em ratos submetidos ou não ao pneumoperitônio com CO2, sob anestesia com ou sem intubação intratraqueal. MÉTODO: Ratos machos (n = 40, albinos, com peso médio de 300g, idade de três meses, foram randonizados em quatro grupos: GA - anestesia com intubação endotraqueal por uma hora e com pneumoperitônio de 4mmHg de CO2; GB - anestesia sem intubação endotraqueal por uma hora e com pneumoperitônio de 4mmHg de CO2; GC - anestesia sem intubação endotraqueal por uma hora e sem pneumoperitônio; GD - anestesia com intubação endotraqueal por uma hora, sem pneumoperitônio. Foram registrados os valores da pressão arterial média (PAM, pressão parcial de gás carbônico (pCO2, freqüência cardíaca (FC, freqüência respiratória (FR, pressão venosa central (PVC, potencial hidrogeniônico acidose (pH, saturação de oxigênio periférico (spO2, bicarbonato (HCO3- e saturação de oxigênio no sangue arterial (SO2,. Os dados foram coletados no início do experimento (M0, após 30 minutos (M1 e após 60 minutos (M2. RESULTADOS: Em GA e GC (grupos com pneumoperitônio ocorreu aumento da PAM, PCO2, HCO3-, FR, PVC e uma diminuição do pH, SO2, spO2 e da FC em relação aos animais sem pneumoperitônio. Por outro lado a intubação intratraqueal demonstrou atenuar estas alterações nos animais com até uma hora de anestesia. CONCLUSÃO: A anestesia geral com intubação endotraqueal associada ao pneumoperitônio de 4mmHg, por um período de uma hora, mostrou vantagens do ponto de vista respiratório e hemodinâmico, em relação aos animais com pneumoperitônio e sem intubação e também sobre aqueles com até quatro horas de anestesia, apesar da intubação.
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Scanning Electron Microscope-Cathodoluminescence Analysis of Rare-Earth Elements in Magnets.
Imashuku, Susumu; Wagatsuma, Kazuaki; Kawai, Jun
2016-02-01
Scanning electron microscope-cathodoluminescence (SEM-CL) analysis was performed for neodymium-iron-boron (NdFeB) and samarium-cobalt (Sm-Co) magnets to analyze the rare-earth elements present in the magnets. We examined the advantages of SEM-CL analysis over conventional analytical methods such as SEM-energy-dispersive X-ray (EDX) spectroscopy and SEM-wavelength-dispersive X-ray (WDX) spectroscopy for elemental analysis of rare-earth elements in NdFeB magnets. Luminescence spectra of chloride compounds of elements in the magnets were measured by the SEM-CL method. Chloride compounds were obtained by the dropwise addition of hydrochloric acid on the magnets followed by drying in vacuum. Neodymium, praseodymium, terbium, and dysprosium were separately detected in the NdFeB magnets, and samarium was detected in the Sm-Co magnet by the SEM-CL method. In contrast, it was difficult to distinguish terbium and dysprosium in the NdFeB magnet with a dysprosium concentration of 1.05 wt% by conventional SEM-EDX analysis. Terbium with a concentration of 0.02 wt% in an NdFeB magnet was detected by SEM-CL analysis, but not by conventional SEM-WDX analysis. SEM-CL analysis is advantageous over conventional SEM-EDX and SEM-WDX analyses for detecting trace rare-earth elements in NdFeB magnets, particularly dysprosium and terbium.
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Contrast of Backscattered Electron SEM Images of Nanoparticles on Substrates with Complex Structure
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Thomas Kowoll
2017-01-01
Full Text Available This study is concerned with backscattered electron scanning electron microscopy (BSE SEM contrast of complex nanoscaled samples which consist of SiO2 nanoparticles (NPs deposited on indium-tin-oxide covered bulk SiO2 and glassy carbon substrates. BSE SEM contrast of NPs is studied as function of the primary electron energy and working distance. Contrast inversions are observed which prevent intuitive interpretation of NP contrast in terms of material contrast. Experimental data is quantitatively compared with Monte-Carlo- (MC- simulations. Quantitative agreement between experimental data and MC-simulations is obtained if the transmission characteristics of the annular semiconductor detector are taken into account. MC-simulations facilitate the understanding of NP contrast inversions and are helpful to derive conditions for optimum material and topography contrast.
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Characterising palladium-silver and palladium-nickel alloy membranes using SEM, XRD and PIXE
International Nuclear Information System (INIS)
Keuler, J.N.; Lorenzen, L.; Sanderson, R.D.; Prozesky, V.; Przybylowicz, W.J.
1999-01-01
Palladium alloy membranes were prepared by successive electroless plating steps on an alumina-zirconia support membrane. Palladium, silver and nickel were deposited in layers and then the metal films were heat treated for 5 h in a hydrogen atmosphere at 650 deg. C. The topography of the metal coatings and cross-sections of the films (before and after heating) were characterised using scanning electron microscopy (SEM). XRD was used to determine the crystal phase of the alloy coatings. Both SEM and XRD provide only surface information and therefore micro-PIXE was used to extract depth information of the alloy coating. Concentration profiles across the thickness of the films were constructed to determine penetration of the coating into the support membrane pores during electroless plating and to investigate diffusion of coated layers during the heating step
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Mechanisms of biliary stent clogging: confocal laser scanning and scanning electron microscopy.
van Berkel, A M; van Marle, J; Groen, A K; Bruno, M J
2005-08-01
Endoscopic insertion of plastic biliary endoprostheses is a well-established treatment for obstructive jaundice. The major limitation of this technique is late stent occlusion. In order to compare events involved in biliary stent clogging and identify the distribution of bacteria in unblocked stents, confocal laser scanning (CLS) and scanning electron microscopy (SEM) were carried out on two different stent materials - polyethylene (PE) and hydrophilic polymer-coated polyurethane (HCPC). Ten consecutive patients with postoperative benign biliary strictures were included in the study. Two 10-Fr stents 9 cm in length, one made of PE and the other of HCPC, were inserted. The stents were electively exchanged after 3 months and examined using CLS and SEM. No differences were seen between the two types of stent. The inner stent surface was covered with a uniform amorphous layer. On top of this layer, a biofilm of living and dead bacteria was found, which in most cases was unstructured. The lumen was filled with free-floating colonies of bacteria and crystals, surrounded by mobile laminar structures of mucus. An open network of large dietary fibers was seen in all of the stents. The same clogging events occurred in both PE and HCPC stents. The most remarkable observation was the identification of networks of large dietary fibers, resulting from duodenal reflux, acting as a filter. The build-up of this intraluminal framework of dietary fibers appears to be a major factor contributing to the multifactorial process of stent clogging.
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Investigação sobre o desamparo aprendido em humanos
Mariana Januario Samelo
2008-01-01
A literatura sobre o desamparo aprendido utilizando humanos como participantes de pesquisa, tem encontrado dificuldades metodologicas. O presente experimento teve como objetivo geral estabelecer um procedimento que permitisse controle experimental suficiente para verificacao do efeito de uma historia de incontrolabilidade, com e sem feedback de erro, sobre a aprendizagem de uma nova resposta operante em sujeitos humanos. Estudantes universitarios foram divididos em quatro grupos (n=10), deno...
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Ramshorst, M.C.J. van; Benedetto, G.L. di; Duvalois, W.; Hooijmeijer, P.A.; Heijden, A.E.D.M. van der
2016-01-01
The failure mechanism of a propellant consisting of hydroxyl terminated poly-butadiene filled with ammonium perchlorate and aluminum (HTPB/AP/Al) was determined by performing in-situ uniaxial tensile tests in a scanning electron microscope (SEM). The experimental test plan contained uniaxial tensile
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Stereoscopic and photometric surface reconstruction in scanning electron microscopy
International Nuclear Information System (INIS)
Scherer, S.
2000-01-01
The scanning electron microscope (SEM) is one of the most important devices to examine microscopic structures as it offers images of a high contrast range with a large depth of focus. Nevertheless, three-dimensional measurements, as desired in fracture mechanics, have previously not been accomplished. This work presents a system for automatic, robust and dense surface reconstruction in scanning electron microscopy combining new approaches in shape from stereo and shape from photometric stereo. The basic theoretical assumption for a known adaptive window algorithm is shown not to hold in scanning electron microscopy. A constraint derived from this observation yields a new, simplified, hence faster calculation of the adaptive window. The correlation measure itself is obtained by a new ordinal measure coefficient. Shape from photometric stereo in the SEM is formulated by relating the image formation process with conventional photography. An iterative photometric ratio reconstruction is invented based on photometric ratios of backscatter electron images. The performance of the proposed system is evaluated using ground truth data obtained by three alternative shape recovery devices. Most experiments showed relative height accuracy within the tolerances of the alternative devices. (author)
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Directory of Open Access Journals (Sweden)
Antonio Alberto Lopes
2003-09-01
Full Text Available OBJETIVOS: Avaliar se, no Brasil, o número de anos em tratamento dialítico dos pacientes portadores de estágio final de doença renal (EFDR, com e sem diabetes melito, está relacionado com o risco de morte. MÉTODOS: Análise de dados do Ministério da Saúde do Brasil de 25.952 pacientes com idade superior a 18 anos, portadores de EFDR, que estavam em tratamento dialítico em abril de 1997. Foram registrados os casos de óbito que ocorreram entre abril de 1997 e julho de 2000. Modelos de Cox foram utilizados para estimar o risco relativo (RR da associação entre número de anos em tratamento dialítico e risco de morte. RESULTADOS: O risco de morte foi significantemente menor nos pacientes que estavam em diálise entre 3 e OBJECTIVE: To assess whether, in Brazil, the number of years on dialysis treatment in end-stage renal disease (ESRD patients, with and without diabetes mellitus, relates to mortality risk. METHODS: Analysis of data from the Ministry of Health of Brazil of 25.952 patients older than 18 years who were on dialytic treatment in April 1997. Death cases that occurred from April 1997 to July 2000 were recorded. Cox models were used to estimate the relative risk (RR of the association between years on dialysis and mortality risk. RESULTS: The mortality risk was significantly lower in patients on dialysis between 3 and <10 years as compared with 1 to <2 years (RR between 0.78 and 0.88. With adjustments for age and diabetes the effect of years on dialysis was reduced. In diabetics (n=2.952 the adjusted mortality risk showed a trend to decrease with more years on dialysis. CONCLUSIONS: In Brazil, the mortality risk for ESRD patients decreases with the increasing number of years on dialysis up to approximately 10 years. This finding can be partially explained by the lower mean age and prevalence of diabetes mellitus in patients with more years on dialysis treatment. The effect of years on dialysis on the mortality risk seems to be
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Directory of Open Access Journals (Sweden)
José Manuel Godinho Calado
2008-12-01
Full Text Available A diminuição da perturbação do solo é de extrema importância para a manutenção e preservação dos sistemas agrícolas. Por isso, o estudo realizado neste trabalho tinha como objectivo verificar o aparecimento das plantas espontâneas a partir do solo com e sem perturbação. A população de plantas emergidas inicialmente, no Outono, foi controlada com perturbação do solo através da simulação da mobilização realizada pelo escarificador e sem perturbação do solo em que se aplicou um herbicida total e não residual. A experimentação foi efectuada em solos Mediterrâneos durante quatro anos, com um delineamento experimental em blocos casualizados e oito repetições. De acordo com os resultados, verifica-se que a perturbação do solo efectuada para controlar a flora espontânea no Outono influencia significativamente o aparecimento das plantas em condições mediterrânicas e permite obter maior densidade populacional, que aumenta com o acréscimo da precipitação acumulada. Daqui conclui-se que em sistemas com diminuição da perturbação do solo, como por exemplo, de sementeira directa, é possível decrescer a infestação nas culturas de Outono-Inverno.The reduction of soil disturbance is extremely important for the conservation of soil and thus for the sustainability of agricultural systems. Soil disturbance interferes with a number of soil parameters including its fauna and flora. This paper deals with the comparison of the appearance of spontaneous plants from disturbed and undisturbed soil. A study was conducted to compare the appearance of spontaneous flora in autumn after the simulation of soil tillage by a tine cultivator with the control of the already emerged plants through the application of a total herbicide and without any soil disturbance. The trials were realized on typical Mediterranean soils (Luvisol over a period of four years in a completely randomized block design and with eight replications. The
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International Nuclear Information System (INIS)
Smaali, K.; Faure, J.; El Hdiy, A.; Troyon, M.
2008-01-01
High-resolution electron beam induced current (EBIC) analyses were carried out on a shallow ion implanted p + -n silicon junction in a scanning electron microscope (SEM) and a scanning probe microscope (SPM) hybrid system. With this scanning near-field EBIC microscope, a sample can be conventionally imaged by SEM, its local topography investigated by SPM and high-resolution EBIC image simultaneously obtained. It is shown that the EBIC imaging capabilities of this combined instrument allows the study of p-n junctions with a resolution of about 20 nm
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SEM and AFM studies of dip-coated CuO nanofilms.
Dhanasekaran, V; Mahalingam, T; Ganesan, V
2013-01-01
Cupric oxide (CuO) semiconducting thin films were prepared at various copper sulfate concentrations by dip coating. The copper sulfate concentration was varied to yield films of thicknesses in the range of 445-685 nm by surface profilometer. X-ray diffraction patterns revealed that the deposited films were polycrystalline in nature with monoclinic structure of (-111) plane. The surface morphology and topography of monoclinic-phase CuO thin films were examined using scanning electron microscopy (SEM) and atomic force microscopy (AFM), respectively. Surface roughness profile was plotted using WSxM software and the estimated surface roughness was about ∼19.4 nm at 30 mM molar concentration. The nanosheets shaped grains were observed by SEM and AFM studies. The stoichiometric compound formation was observed at 30 mM copper sulfate concentration prepared film by EDX. The indirect band gap energy of CuO films was increased from 1.08 to 1.20 eV with the increase of copper sulfate concentrations. Copyright © 2012 Wiley Periodicals, Inc.
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Directory of Open Access Journals (Sweden)
Carla Regina Amorim dos Anjos Queiroz
2015-07-01
Full Text Available A Pereskia aculeata Miller é uma hortaliça não convencional cujo consumo pode fornecer à dieta substâncias nutritivas e antioxidantes, ambas com teores influenciados pelas condições de cultivo. Foram cultivadas, a partir de sementes, plantas em sombra artificial, em meia sombra e sem sombra. Avaliou-se o crescimento em termos de massa e unidades estruturais e quantificou-se o resíduo mineral, proteínas, lipídeos, fibra em detergente neutro, fenóis e atividade antioxidante. Há influência do sombreamento no crescimento, no teor de nutrientes e metabólitos secundários. As plantas sem sombra apresentaram maior altura, número de folhas, diâmetro do colo, massa seca de caules e folhas e atividade antioxidante. As plantas totalmente sombreadas apresentaram maiores teores de cinzas, lipídeos e proteínas. Para todos os parâmetros avaliados os teores quantificados em folhas foram maiores que em caules.
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Directory of Open Access Journals (Sweden)
J. S. Soares
2017-12-01
Full Text Available O cultivo in vitro de orquídeas possibilita elevadas porcentagens de germinação, quando comparadas a germinação natural dessas espécies, pois suas sementes possuem pouca ou nenhuma reserva nutritiva. Objetivou-se avaliar diferentes volumes de suspensão de sementes na propagação in vitro de Dendrobium nobile Lindl. var. nobilius e var. comet king em meio alternativo, sem subcultivos. Foram utilizadas 0,02 g de sementes de cada planta e desinfestadas em solução de hipoclorito de sódio a 0,8%, por 15 minutos, sendo diluídas em água estéril até completar 60 mL. Em ambiente asséptico, procedeu-se a semeadura in vitro. Foram pipetados 2, 3 ou 4 mL de cada suspensão de sementes em frascos de vidro de 600mL providos de tampa metálica e contendo 80 mL do meio de cultura alternativo. As culturas foram transferidas para sala de crescimento com temperatura e fotoperíodo controlados (25 ± 2 ºC; 16 horas permanecendo por seis meses nessas condições. O maior número de sementes potencialmente viáveis (426 mg-1 foi observado em D. nobile var. nobilius, enquanto D. nobile var. comet king apresentou 164 mg-1 sementes potencialmente viáveis. A variedade nobilius apresentou maiores resultados no número de plantas total e de plantas vivas, número de folhas, número e diâmetro de pseudobulbos e comprimento da maior raiz, característica dessa variedade, que é mais vigorosa. A inoculação de 2mL foi mais eficiente para a micropropagação das duas plantas, havendo menos concorrência entre as plântulas no frasco.
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Directory of Open Access Journals (Sweden)
Luciana Oliveira Correia
2007-12-01
Full Text Available O trabalho apresenta pesquisa etnográfica desenvolvida com crianças moradoras de um acampamento do Movimento dos Sem Terra, em Minas Gerais. Pela observação participante do cotidiano infantil e por meio de entrevistas com crianças, buscou-se apreender os significados da vivência da infância no interior de um movimento social organizado. No escopo deste artigo, no diálogo com os refereciais teórico-metodológicos da sociologia da infância, foram analisadas três das entrevistas realizadas, de forma a destacar a singularidade dos processos socializatórios vividos por tais sujeitos, definidos por duas categorias identitárias: geração e inserção em movimentos sociais. Verifica-se que as crianças, em sua ação coletiva voltada para a atividade do brincar, buscavam interpretar sua experiência coletiva, lançando mão de elementos da cultura infantil, de forma a elaborar o vivido. Ao mesmo tempo, buscavam estabelecer relações com outros universos sociais, tais como a escola, de maneira a construir novos espaços de sociabilidade.This papper describes an etnographical research realized with a group of childs from the Movimento dos Sem Terra of Minas Gerais/Brazil. Using metodologies strategies like participative observation and interviews, we focused the signification of childhood experience inside an organized social movement. According to that, in dialogue with the teorical references of Childhood Sociology, the research analises their identity construction process, considering two central categories: generation and insertion in social movements. The children, in coletive action centered on playing, uses it to interpret their social universe, elaborating their own experience. In other hand, they tried to construct new relations with another social universes, like school, in order to increase their sociabilities.
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Desenvolvimento de corantes naturais para uso em plástico
Sérgio Roberto Knorr Velho
2016-01-01
O trabalho buscou identificar se o intemperismo acelerado Xênon, utilizando a norma ASTM D4452-12, em corantes naturais encapsulados em matriz de sílica pelo processo sol gel com o uso de alcóxidos, conforme descrito pela patente INPI BR 10 2013 0219835, e injetadas em matriz de policloreto de polivinila (PVC) preservam as características de cor original dos corantes. Utilizou-se comparação dos mesmos corantes naturais – carmim, curcuma, índigo e urucum – sem encapsulamento e com encapsulamen...
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The Scanning Electron Microscope As An Accelerator For The Undergraduate Advanced Physics Laboratory
International Nuclear Information System (INIS)
Peterson, Randolph S.; Berggren, Karl K.; Mondol, Mark
2011-01-01
Few universities or colleges have an accelerator for use with advanced physics laboratories, but many of these institutions have a scanning electron microscope (SEM) on site, often in the biology department. As an accelerator for the undergraduate, advanced physics laboratory, the SEM is an excellent substitute for an ion accelerator. Although there are no nuclear physics experiments that can be performed with a typical 30 kV SEM, there is an opportunity for experimental work on accelerator physics, atomic physics, electron-solid interactions, and the basics of modern e-beam lithography.
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Quantitative Analysis of Micro-porosity of Eco-material by Using SEM Technique
Institute of Scientific and Technical Information of China (English)
ZHANG Ji-ru; LIU Yuan-zhi; LIU Zu-de
2004-01-01
Microstructure of the eco-material combining vegetation recovery with slope protection is important for determining plant-growing properties.Several techniques for analyzing the eco-material microstructure are presented,including the freeze-cut-drying method of preparing samples for scanning electronic microscopy (SEM),the SEM image processing technique and quantifying analysis method of the SEM images,and etc.The aggregates and pores in SEM images are identified using the different mathematics operators,and their effects are compared.The areas of aggregates and pores are obtained using the operator of morphology,and the influences of different thresholds in image segmentation are also discussed.The results show that the method,in which the variation of non-maximum grey-level gradient is limited,improves the effect of edge detections due to a weak distinction existing at the edge between the aggregates and pores in image.The determination of the threshold should combine the image characteristic with filling operation,so as to assure the precision of the image analysis,in which the contact-segmentation is the simplest and most effective method.The results also show that the pore areas in eco-materials are generally larger than those in the correlative soils,and their increment is large as soil fabric being fine.These differences are related to admixture of expansive perliticThe operator of morphology provides a new method for the image analysis of other porous material microstructure such as soils and concretes.
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Directory of Open Access Journals (Sweden)
Eleutério Junior José
2001-01-01
Full Text Available Objetivo: avaliar a expressão de receptores de estrógeno (RE e progesterona (RP em esfregaços de sedimento de fluido peritoneal em pacientes com endometriose, comparando-a com a de mulheres sem endometriose. Métodos: foi realizado imunocitoquímica para RE e RP em esfregaços de sedimento de fluido peritoneal em 19 casos de endometriose e 7 sem endometriose (controle. Os dados foram submetidos ao teste t de Student para análise estatística. Resultados: em 84,6% dos casos de pacientes com endometriose, células tipo endometrial expressaram RE, numa média de 4,1%, ao passo que nos casos sem endometriose foi positivo em 42,9%, com uma expressão média de 4,5% (p = 0,1706. RP foi expresso apenas em um caso, com endometriose, com história de rotura de endometrioma. Conclusões: não houve diferença da expressão de RE entre os casos de endometriose e os casos-controle, observando-se um comportamento distinto em tecidos. Um mais aprofundado estudo deve ser feito para melhor avaliar o enigmático mecanismo envolvido na manifestação de receptores hormonais em células esfoliadas.
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Directory of Open Access Journals (Sweden)
Aline Moreira André
2017-08-01
Full Text Available Os pesquisadores americanos Nordoff, Robbins e Marcus (2007 desenvolveram em 1964 a Escala de Comunicabilidade Musical. Utilizaram, nessa escala, instrumentos musicais, a voz e movimentos corporais para estudar em crianças os diferentes aspectos da capacidade de comunicação através da música. Objetivamos, nesta pesquisa, avaliar a tradução realizada da Escala de Comunicabilidade Musical e de seu manual explicativo para o português brasileiro. Como metodologia, realizamos 3 etapas do Modelo Universalista de Validação desenvolvido por Herdman, Fox-Hushby e Badia (1998 denominadas equivalência de itens, equivalência semântica e equivalência operacional. Participaram desse estudo 4 tradutores na etapa inicial e 10 avaliadores no processo de avaliação da tradução. Foram utilizados como instrumentos, a Escala de Comunicabilidade Musical de Nordoff Robbins e seu respectivo manual explicativo. Foi elaborada especialmente para este estudo uma Ficha para análise das Traduções e um Questionário de Análise da Equivalência de Itens, Semântica e Operacional. De acordo com a análise das respostas coletadas dos avaliadores, a tradução dessa escala apresenta linguagem compreensível, seus itens são pertinentes para o contexto brasileiro e podem contribuir para futuras pesquisas em musicoterapia e em música.
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Fast-scan em with digital image processing for dynamic experiments
Charles W. McMillin; Fred C. Billingsley; Robert E. Frazer
1973-01-01
The recent introduction of accessory instrumentation capable of display at television scan rates suggests a broadened application for the scanning electron microscope - the direct observation of motion (dynamic events) at magnifactions otherwise unattainable. In one illustrative experiment, the transverse surface of southern pine was observed when subjected to large...
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Directory of Open Access Journals (Sweden)
Sandra Cristina T. Camarota
1992-03-01
Full Text Available Trezentas e oitenta e cinco amostras fecais provenientes de crianças na faixa etária de até 11 anos, sem sintomatologia de diarréia, foram estudadas objetivando-se a detecção de rotavirus. Desta amostragem, 268foram obtidas de crianças habitantes de creches e 117 de crianças atendidas no ambulatório do Hospital Lúcio Rebelo de Goiânia-Goiás. Todas as amostrasforam analisadas através da técnica de eletroforese em gel de poliacrilamida (EGPA- SDS, e 89 foram também analisadas pelo ensaio imunoenzimático adaptado para rotavirus e adenovirus (E1ARA. Rotavirus e adenovirus só foram detectados nas crianças atendidas no ambulatório, num percentual de 1,7% e 1,6% respectivamente, não havendo nenhuma positividade nas crianças de creches. Ambos os vírus ocorrerarh na faixa etária de 1 a 2 anos.
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Contact detection for nanomanipulation in a scanning electron microscope.
Ru, Changhai; To, Steve
2012-07-01
Nanomanipulation systems require accurate knowledge of the end-effector position in all three spatial coordinates, XYZ, for reliable manipulation of nanostructures. Although the images acquired by a scanning electron microscope (SEM) provide high resolution XY information, the lack of depth information in the Z-direction makes 3D nanomanipulation time-consuming. Existing approaches for contact detection of end-effectors inside SEM typically utilize fragile touch sensors that are difficult to integrate into a nanomanipulation system. This paper presents a method for determining the contact between an end-effector and a target surface during nanomanipulation inside SEM, purely based on the processing of SEM images. A depth-from-focus method is used in the fast approach of the end-effector to the substrate, followed by fine contact detection. Experimental results demonstrate that the contact detection approach is capable of achieving an accuracy of 21.5 nm at 50,000× magnification while inducing little end-effector damage. Copyright © 2012 Elsevier B.V. All rights reserved.
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Directory of Open Access Journals (Sweden)
Yanli Wang
2012-06-01
Full Text Available The antibacterial activity and mechanism of two kinds of chitosan were investigated against twelve <em>Xanthomonas> strains recovered from <em>Euphorbia pulcherrimaem>. Results indicated that both chitosans markedly inhibited bacterial growth based on OD loss. Furthermore, the release of DNA and RNA from three selected strains was increased by both chitosans. However, the release of intracellular proteins was inhibited by both chitosans at different concentration and incubation times, except chitosan A at 0.1 mg/mL for 0.5 h incubation and 0.2 mg/mL for 2.0 h incubation increased the release of proteins, indicating the complexity of the interaction and cell membranes, which was affected by incubation time, bacterial species, chitosan type and concentration. Transmission electron microscopic observations revealed that chitosan caused changes in protoplast concentration and surface morphology. In some cells, the membranes and walls were badly distorted and disrupted, while other cells were enveloped by a thick and compact ribbon-like layer. The contrary influence on cell morphology may explain the differential effect in the release of material. In addition, scanning electron microscope and biofilm formation test revealed that both chitosans removed biofilm biomass. Overall, this study showed that membrane and biofilm play an important role in the antibacterial mechanism of chitosan.
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Search Engine Marketing (SEM): Financial & Competitive Advantages of an Effective Hotel SEM Strategy
Leora Halpern Lanz
2015-01-01
Search Engine Marketing and Optimization (SEO, SEM) are keystones of a hotels marketing strategy, in fact research shows that 90% of travelers start their vacation planning with a Google search. Learn five strategies that can enhance a hotels SEO and SEM strategies to boost bookings.
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Electron Microscopy of Nanostructures in Cells
DEFF Research Database (Denmark)
Købler, Carsten
with cells is therefore increasingly more relevant from both an engineering and a toxicological viewpoint. My work involves developing and exploring electron microscopy (EM) for imaging nanostructures in cells, for the purpose of understanding nanostructure-cell interactions in terms of their possibilities...... in science and concerns in toxicology. In the present work, EM methods for imaging nanostructure-cell interactions have been explored, and the complex interactions documented and ordered. In particular the usability of the focused ion beam scanning electron microscope (FIB-SEM) was explored. Using EM...... in literature. Furthermore, EM proved valuable as it revealed an unnoticed CNT effect. FIB-SEM helped establish that the effect was linked to eosionophilic crystalline pneumonia (ECP)....
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A Comparative Scanning Electron Microscopy Evaluation of Smear ...
African Journals Online (AJOL)
2018-02-07
Feb 7, 2018 ... The aim of the present study was to compare the efficacy of chitosan and MTAD for the smear layer removal from the root canal through a scanning electron microscope (SEM). Thirty teeth were randomly divided into three groups according to the final irrigants: 0.2% chitosan, MTAD, saline (control group).
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A Comparative Scanning Electron Microscopy Evaluation of Smear ...
African Journals Online (AJOL)
The aim of the present study was to compare the efficacy of chitosan and MTAD for the smear layer removal from the root canal through a scanning electron microscope (SEM). Thirty teeth were randomly divided into three groups according to the final irrigants: 0.2% chitosan, MTAD, saline (control group). After the ...
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O Planejamento Estratégico sem plano: uma análise do empreendedorismo urbano no Brasil
Directory of Open Access Journals (Sweden)
Eugênio Silva
2012-12-01
Full Text Available O modelo de planejamento estratégico de cidades chega à América Latina, passando a ser adotado em cidades brasileiras, com a formulação de planos estratégicos, desde a década de 1990. Em muitas cidades, porém, o padrão de produção da cidade não se deu de acordo com o modelo adotado internacionalmente, mas desenvolveram uma espécie de “planejamento estratégico sem plano” ou “empreendedorismo periférico”, no qual buscam construir atributos para qualificarem sua inserção no cenário competitivo internacional e regional, através da imitação de outros centros urbanos.
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In-SEM Raman microspectroscopy coupled with EDX - a case study of uranium reference particles
International Nuclear Information System (INIS)
Stefaniak, Elzbieta A.; Pointurier, Fabien; Marie, Olivier; Truyens, Jan; Aregbe, Yetunde
2014-01-01
Information about the molecular composition of airborne uranium-bearing particles may be useful as an additional tool for nuclear safeguards. In order to combine the detection of micrometer-sized particles with the analysis of their molecular forms, we used a hybrid system enabling Raman microanalysis in high vacuum inside a SEM chamber (SEM-SCA system). The first step involved an automatic scan of a sample to detect and save coordinates of uranium particles, along with X-ray microanalysis. In the second phase, the detected particles were relocated in a white light image and subjected to Raman microanalysis. The consecutive measurements by the two beams showed exceptional fragility of uranium particles, leading to their ultimate damage and change of uranium oxidation state. We used uranium reference particles prepared by hydrolysis of uranium hexafluoride to test the reliability of the Raman measurements inside the high vacuum. The results achieved by the hybrid system were verified by using a standalone Raman micro spectrometer. When deposited on exceptionally smooth substrates, uranyl fluoride particles smaller than 1000 nm could successfully be analyzed with the SEM-SCA system. (authors)
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Qin, Shengyong; Kim, Tae-Hwan; Wang, Zhouhang; Li, An-Ping
2012-06-01
The wide variety of nanoscale structures and devices demands novel tools for handling, assembly, and fabrication at nanoscopic positioning precision. The manipulation tools should allow for in situ characterization and testing of fundamental building blocks, such as nanotubes and nanowires, as they are built into functional devices. In this paper, a bottom-up technique for nanomanipulation and nanofabrication is reported by using a 4-probe scanning tunneling microscope (STM) combined with a scanning electron microscope (SEM). The applications of this technique are demonstrated in a variety of nanosystems, from manipulating individual atoms to bending, cutting, breaking carbon nanofibers, and constructing nanodevices for electrical characterizations. The combination of the wide field of view of SEM, the atomic position resolution of STM, and the flexibility of multiple scanning probes is expected to be a valuable tool for rapid prototyping in the nanoscience and nanotechnology.
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Anestesia para craniotomia em paciente acordado: relato de caso
Directory of Open Access Journals (Sweden)
Nelson Davi Bolzani
2013-12-01
Full Text Available JUSTIFICATIVA E OBJETIVOS: Alguns procedimentos intracranianos são possíveis com pacientes acordados e os desafios vão da cooperação do paciente até a homeostasia. O objetivo é apresentar um caso de cirurgia intracraniana para exérese de tumor em lobo parietal esquerdo com o paciente em estado vígil. RELATO DE CASO: Após seleção do paciente e preparo psicológico, foi esclarecida e aceita a proposta de exérese de lesão parietal esquerda em estado vígil. Administraram-se propofol e remifentanil em perfusão contínua para manter o escore de Ramsay entre 2-3. Foi feito um bloqueio bilateral do escalpo com ropivacaína. Foi instalado o fixador de Mayfield e os campos cirúrgicos foram ajustados para manter vias aéreas e olhos acessíveis para o mapeamento com eletroestimulação e exérese da lesão. Para incisão da dura-máter foi aplicada uma compressa com lidocaína 2% por três minutos. A cirurgia transcorreu sem intercorrências. O paciente recebeu alta hospitalar no sétimo dia de internação sem apresentar complicação. CONCLUSÃO: Apesar de ser um desafio manter analgesia e estabilidade hemodinâmica com o paciente acordado, a infusão alvo-controlada do propofol estabeleceu o nível de consciência desejado; a do remifentanil titulou a analgesia e a sedação sem o acúmulo da droga e o bloqueio com a ropivacaína, uma analgesia satisfatória. Concluímos que a técnica anestésica foi satisfatória para nosso paciente.
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O plantão noturno em anestesia reduz a latência ao sono
Mathias, Lígia Andrade da Silva Telles; Coelho, Christina Morotomi Funatsu; Vilela, Elizabeth Pricoli; Vieira, Joaquim Edson; Pagnocca, Marcelo Lacava
2004-01-01
JUSTIFICATIVA E OBJETIVOS: Os médicos em geral, os anestesiologistas em particular, têm jornadas de trabalho prolongadas. Os residentes de Anestesiologia podem apresentar fadiga e estresse significativos. O objetivo deste trabalho foi verificar, em residentes de primeiro e segundo anos a latência do sono em períodos após plantão. MÉTODO: Foram avaliados 11 residentes em situações distintas: às 7 horas da manhã, após noite de sono normal (> 7h), sem plantão nos 3 dias anteriores (M1); às 7 hor...
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Directory of Open Access Journals (Sweden)
Karina Saraiva Schröder
2009-04-01
Full Text Available Este artigo pretende mostrar a relação enunciativo-argumentativa do locutor com seu dizer. O estudo insere-se no quadro teórico da Argumentação na Língua, desenvolvido por Ducrot e colaboradores, o qual postula que o sentido está na língua e é argumentativo. Ao aplicar os conceitos de polifonia e blocos semânticos – forma atual da teoria – a um conto de Edgar Allan Poe, buscamos verificar, metodologicamente, como a organização argumentativa em blocossemânticos orienta o interlocutor à unidade de sentido.The purpose of this paper is to demonstrate the argumentative relation a speaker holds with his saying. This is done within the framework of Theory of Argumentation within Language developed by Ducrot and collaborators, which postulates that meaning is in the language and that it is argumentative. By applying the concepts of polyphony and semantic blocks – the current stage of the theory – to a short story by Edgar Allan Poe, we intend to verify in what way the argumentative organization in semantic blocks guides the reader to a unity of meaning.
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Directory of Open Access Journals (Sweden)
Antonio Alceu dos Santos
2012-06-01
Full Text Available Este artigo relata um caso de retransplante cardíaco sem o uso de hemoderivados, em uma criança de 6 anos, com miocardiopatia dilatada grave, após rejeição crônica do enxerto e refratária ao tratamento clínico. Para evitar transfusão sanguínea nessa cirurgia, foi realizado planejamento multidisciplinar, que envolveu o uso de eritropoietina no pré-operatório, hemodiluição normovolêmica aguda e recuperação de sangue autólogo no intraoperatório (cell saver, bem como hemostasia meticulosa e redução de flebotomias no pós-operatório.This article reports a case of a cardiac retransplantation without the use of blood products, in a 6 year old, with severe dilated cardiomyopathy after chronic graft rejection and refractory to clinical treatment. To avoid a blood transfusion in this surgery a multidisciplinary approach was planned, which involved the use of preoperative erythropoietin, acute normovolemic hemodilution and intraoperative cell savage with autologous blood recovery system, as well as a meticulous hemostasis and reduced postoperative phlebotomy.
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Search Engine Marketing (SEM: Financial & Competitive Advantages of an Effective Hotel SEM Strategy
Directory of Open Access Journals (Sweden)
Leora Halpern Lanz
2015-05-01
Full Text Available Search Engine Marketing and Optimization (SEO, SEM are keystones of a hotels marketing strategy, in fact research shows that 90% of travelers start their vacation planning with a Google search. Learn five strategies that can enhance a hotels SEO and SEM strategies to boost bookings.
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Ng, Siew Cheok; Abu Osman, Noor Azuan
2014-01-01
This paper investigated the effects of critical-point drying (CPD) and hexamethyldisilazane (HMDS) sample preparation techniques for cervical cells on field emission scanning electron microscopy and energy dispersive X-ray (FE-SEM/EDX). We investigated the visualization of cervical cell image and elemental distribution on the cervical cell for two techniques of sample preparation. Using FE-SEM/EDX, the cervical cell images are captured and the cell element compositions are extracted for both sample preparation techniques. Cervical cell image quality, elemental composition, and processing time are considered for comparison of performances. Qualitatively, FE-SEM image based on HMDS preparation technique has better image quality than CPD technique in terms of degree of spread cell on the specimen and morphologic signs of cell deteriorations (i.e., existence of plate and pellet drying artifacts and membrane blebs). Quantitatively, with mapping and line scanning EDX analysis, carbon and oxygen element compositions in HMDS technique were higher than the CPD technique in terms of weight percentages. The HMDS technique has shorter processing time than the CPD technique. The results indicate that FE-SEM imaging, elemental composition, and processing time for sample preparation with the HMDS technique were better than CPD technique for cervical cell preparation technique for developing computer-aided screening system. PMID:25610902
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Fundamentals of overlay measurement and inspection using scanning electron-microscope
Kato, T.; Okagawa, Y.; Inoue, O.; Arai, K.; Yamaguchi, S.
2013-04-01
Scanning electron-microscope (SEM) has been successfully applied to CD measurement as promising tools for qualifying and controlling quality of semiconductor devices in in-line manufacturing process since 1985. Furthermore SEM is proposed to be applied to in-die overlay monitor in the local area which is too small to be measured by optical overlay measurement tools any more, when the overlay control limit is going to be stringent and have un-ignorable dependence on device pattern layout, in-die location, and singular locations in wafer edge, etc. In this paper, we proposed new overlay measurement and inspection system to make an effective use of in-line SEM image, in consideration of trade-off between measurement uncertainty and measurement pattern density in each SEM conditions. In parallel, we make it clear that the best hybrid overlay metrology is in considering each tool's technology portfolio.
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Cengiz, Esra; Kurtulmus-Yilmaz, Sevcan; Ulusoy, Nuran; Deniz, Sule Tugba; Yuksel-Devrim, Ece
2016-05-01
The aim of this study was to investigate the effect of hydrogen peroxide (HP) and carbamide peroxide (CP) on the surface roughness of five different composite resins using profilometer and scanning electron microscope (SEM). Thirty-six specimens (1 mm thick, 10 mm in diameter) of five composite resins were fabricated. Each composite group was equally divided into three subgroups as control, CP and HP. In control group, specimens were stored in daily refreshed distilled water during the 14-day testing period. In other groups, 10% HP (Opalescence Treswhite) and 10% CP (Opalescence PF) were applied and surface roughness values (Ra) of each specimen were measured with a profilometer at the end of 14 days. Additionally, SEM analysis was performed to evaluate the surface deformations of composite resins. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Ra values of composite groups exposed to bleaching agents were statistically higher than control group (p composite group while SEM micrographs showed higher surface alterations at HP group compared to CP. Among the composite resins tested, Ceram-X Mono revealed the lowest Ra values after CP and HP applications as seen at SEM images. Home bleaching agents increased the surface roughness of all composites. Except CP applied Ceram-X mono specimens, Ra values of all composite resins evaluated in this study exceeded the critical limit of 0.2 μm. Ceram-X mono was the least affected composite material after bleaching application. SCANNING 38:277-283, 2016. © 2016 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.
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Scanning electron microscopy of individual nanoparticle bio-markers in liquid
Energy Technology Data Exchange (ETDEWEB)
Liv, Nalan, E-mail: n.liv@tudelft.nl; Lazić, Ivan; Kruit, Pieter; Hoogenboom, Jacob P.
2014-08-01
We investigated SEM imaging of nanoparticle biomarkers suspended below a thin membrane, with the ultimate goal of integrating functional fluorescence and structural SEM measurements of samples kept at ambient or hydrated conditions. In particular, we investigated how resolving power in liquid SEM is affected by the interaction of the electron beam with the membrane. Simulations with the Geant4-based Monte Carlo scheme developed by Kieft and Bosch (2008) [1] are compared to experimental results with suspended nanoparticles. For 20 nm and 50 nm thin membranes, we found a beam broadening of 1.5 nm and 3 nm, respectively, with an excellent agreement between simulations and experiments. 15 nm Au nanoparticles and bio-functionalized core-shell quantum dots can be individually resolved in denser clusters. We demonstrated the imaging of single EGF-conjugated quantum dots docked at filopodia during cellular uptake with both fluorescence microscopy and SEM simultaneously. These results open novel opportunities for correlating live fluorescence microscopy with structural electron microscopy. - Highlights: • We investigate the achievable resolution in liquid scanning electron microscopy (SEM). • We demonstrate liquid SEM imaging of individual fluorescent nanoparticle bio-markers • We show imaging of cellular QDot uptake with simultaneous fluorescence microscopy and SEM. • The positions of individual QDots can be resolved with details on cellular structure.
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Scanning electron microscopy of individual nanoparticle bio-markers in liquid
International Nuclear Information System (INIS)
Liv, Nalan; Lazić, Ivan; Kruit, Pieter; Hoogenboom, Jacob P.
2014-01-01
We investigated SEM imaging of nanoparticle biomarkers suspended below a thin membrane, with the ultimate goal of integrating functional fluorescence and structural SEM measurements of samples kept at ambient or hydrated conditions. In particular, we investigated how resolving power in liquid SEM is affected by the interaction of the electron beam with the membrane. Simulations with the Geant4-based Monte Carlo scheme developed by Kieft and Bosch (2008) [1] are compared to experimental results with suspended nanoparticles. For 20 nm and 50 nm thin membranes, we found a beam broadening of 1.5 nm and 3 nm, respectively, with an excellent agreement between simulations and experiments. 15 nm Au nanoparticles and bio-functionalized core-shell quantum dots can be individually resolved in denser clusters. We demonstrated the imaging of single EGF-conjugated quantum dots docked at filopodia during cellular uptake with both fluorescence microscopy and SEM simultaneously. These results open novel opportunities for correlating live fluorescence microscopy with structural electron microscopy. - Highlights: • We investigate the achievable resolution in liquid scanning electron microscopy (SEM). • We demonstrate liquid SEM imaging of individual fluorescent nanoparticle bio-markers • We show imaging of cellular QDot uptake with simultaneous fluorescence microscopy and SEM. • The positions of individual QDots can be resolved with details on cellular structure
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A hybrid 3D SEM reconstruction method optimized for complex geologic material surfaces.
Yan, Shang; Adegbule, Aderonke; Kibbey, Tohren C G
2017-08-01
Reconstruction methods are widely used to extract three-dimensional information from scanning electron microscope (SEM) images. This paper presents a new hybrid reconstruction method that combines stereoscopic reconstruction with shape-from-shading calculations to generate highly-detailed elevation maps from SEM image pairs. The method makes use of an imaged glass sphere to determine the quantitative relationship between observed intensity and angles between the beam and surface normal, and the detector and surface normal. Two specific equations are derived to make use of image intensity information in creating the final elevation map. The equations are used together, one making use of intensities in the two images, the other making use of intensities within a single image. The method is specifically designed for SEM images captured with a single secondary electron detector, and is optimized to capture maximum detail from complex natural surfaces. The method is illustrated with a complex structured abrasive material, and a rough natural sand grain. Results show that the method is capable of capturing details such as angular surface features, varying surface roughness, and surface striations. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Study of SEM induced current and voltage contrast modes to assess semiconductor reliability
Beall, J. R.
1976-01-01
The purpose of the scanning electron microscopy study was to review the failure history of existing integrated circuit technologies to identify predominant failure mechanisms, and to evaluate the feasibility of their detection using SEM application techniques. The study investigated the effects of E-beam irradiation damage and contamination deposition rates; developed the necessary methods for applying the techniques to the detection of latent defects and weaknesses in integrated circuits; and made recommendations for applying the techniques.
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Directory of Open Access Journals (Sweden)
Karen Cristina Leite Silva
2015-06-01
Full Text Available The use of genetic diversity as a basis for identifying combinations which are superior to the parents, with a greater heterozygosity, is important in view of the difficulty when selecting promising genotypes for a breeding program. Given the above, the aim of this work was to evaluate genetic diversity in maize genotypes with and without a topdressing of nitrogen fertiliser, using characteristics of the growth stage of the crop. Two field experiments were carried out in Gurupi, in the south of the state of Tocantins, Brazil (TO, one with and another without a topdressing of N fertilizer (1 - no N topdressing, 2 - 150 kg N ha-1. The treatments consisted of 12 genotypes (six open-pollinated populations, and six S5 strains. In applying the technique of clustering to the genotypes, the Generalised Mahalanobis Distance (D2 was adopted as dissimilarity measure. To establish similar groups, the agglomerative hierarchical method of optimisation proposed by Tocher was applied. In addition, Singh’s criterion was used to quantify the relative contribution to genetic divergence of the characteristics under evaluation. The characteristics, Chlorophyll-a and total chlorophyll, displayed the greatest contribution to genetic divergence, when there was no topdressing of nitrogen fertiliser and with the use of 150 kg N ha-1 respectively. A topdressing of nitrogen influenced both the vegetative development of the genotypes, and the expression of their genetic variability. = A utilização da divergência genética como base para a identificação de combinações superiores aos progenitores, apresentando maior heterozigose, faz-se importante diante da dificuldade de escolha de genótipos promissores em um programa de melhoramento. Com base no exposto, objetivou-se com este trabalho avaliar a divergência genética de genótipos de milho com e sem adubação nitrogenada em cobertura, utilizando características do estágio vegetativo da cultura, no sul do Estado
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Hänßler, Olaf C.
2018-01-01
The work covers a multimodal microscope technology for the analysis, manipulation and transfer of materials and objects in the submicrometer range. An atomic force microscope (AFM) allows imaging of the surface topography and a Scanning Microwave Microscope (SMM) detects electromagnetic properties, both operating in a Scanning Electron Microscope (SEM). The described technology demonstrator allows to observe the region-of-interest live with the SEM, while at the same time a characterization w...
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Directory of Open Access Journals (Sweden)
Rubens Camargo Siqueira
2007-03-01
Full Text Available PURPOSE: To compare the surgical results of vitrectomy with and without scleral buckling for rhegmatogenous retinal detachment (RD. METHODS: Fifty-one patients with rhegmatogenous retinal detachment with proliferative vitreoretinopathy (PVR at different stages were submitted to pars plana vitrectomy as the primary surgery, 23 patients (45.09% with scleral buckle (group I and 28 (54.90% without scleral buckle (group II. Visual acuity, anterior segment complications, intraocular pressure, strabismus and retina reattachment rate were evaluated in both groups. RESULTS: The anatomical success and postoperative complications were similar in both groups. Retinal reattachment was achieved in 20 of 23 eyes (87% of group I and in 24 of 28 eyes (85.7% of group II after the initial surgery (p=1.000. Elevated intraocular pressure was noted in 2 eyes (8.7% of group I and 1 eye (3.6% of group II (p=0.583. Corneal abnormalities were seen in 3 eyes (13% of group I and 2 eyes (7.19% of the group II (p=0.647. Visual acuity improved from a preoperative median of 20/200 to a median of 20/100 in group 1 and from 20/400 to 20/100 in group 2; the difference between the two groups was statistically significant (pOBJETIVOS: Comparar os resultados cirúrgicos da vitrectomia com e sem "buckle" escleral para descolamento da retina regmatogênico (DR. MÉTODOS: Cinqüenta e um pacientes com descolamento da retina regmatogênico com proliferação vitreorretiniana (PVR em diferentes estádios foram submetidos a vitrectomia pars plana como cirurgia primária; 23 pacientes (45,09% com buckle escleral (grupo 1 e 28 pacientes (54,90% sem "buckle" escleral (grupo 2. Acuidade visual, complicações do segmento anterior, pressão intra-ocular, estrabismo e razão do redescolamento da retina foram avaliados em ambos os grupos. RESULTADOS: O sucesso anatômico e complicações pós-operatórias foram semelhantes em ambos os grupos. A reaplicação da retina foi obtida em 20 dos 23
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O Marketing de Serviços e suas Implicações para uma Organização sem Fins Lucrativos
Magali Costa Guimarães
2003-01-01
Este estudo restringiu-se em tentar compreender a visão de marketing de serviços dos responsáveis por uma organização sem fins lucrativos. O objetivo centrou-se em conhecer se tais pessoas conhecem quem são, o que desejam e esperam seus clientes, como vêm utilizando os conceitos de marketing e como avaliam a qualidade dos serviços executados na organização à luz da teoria de marketing. O estudo traz algumas reflexões importantes sobre a utilização do marketing de valor para as organizações se...
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Tekçe, Neslihan; Pala, Kansad; Demirci, Mustafa; Tuncer, Safa
2016-11-01
To evaluate changes in surface characteristics of two different resin composites after 1 year of water storage using a profilometer, Vickers hardness, scanning electron microscopy (SEM), and atomic force microscopy (AFM). A total of 46 composite disk specimens (10 mm in diameter and 2 mm thick) were fabricated using Clearfil Majesty Esthetic and Clearfil Majesty Posterior (Kuraray Medical Co, Tokyo, Japan). Ten specimens from each composite were used for surface roughness and microhardness tests (n = 10). For each composite, scanning electron microscope (SEM, n = 2) and atomic force microscope (AFM, n = 1) images were obtained after 24 h and 1 year of water storage. The data were analyzed using two-way analysis of variance and a post-hoc Bonferroni test. Microhardness values of Clearfil Majesty Esthetic decreased significantly (78.15-63.74, p = 0.015) and surface roughness values did not change after 1 year of water storage (0.36-0.39, p = 0.464). Clearfil Majesty Posterior microhardness values were quite stable (138.74-137.25, p = 0.784), and surface roughness values increased significantly (0.39-0.48, p = 0.028) over 1 year. One year of water storage caused microhardness values for Clearfil Majesty Esthetic to decrease and the surface roughness of Clearfil Majesty Posterior increased. AFM and SEM images demonstrated surface detoration of the materials after 1 year and ensured similar results with the quantitative test methods. SCANNING 38:694-700, 2016. © 2016 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.
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Pistas dermatoscópicas para diferenciar a tricotilomania da alopecia areata em placa
Abraham,Leonardo Spagnol; Torres,Fernanda Nogueira; Azulay-Abulafia,Luna
2010-01-01
INTRODUÇÃO: Tricotilomania e alopecia areata em placa possuem características clínicas e dermatoscópicas semelhantes. OBSERVAÇÕES: O exame dermatoscópico da tricotilomania revela densidade capilar diminuída, cabelos fraturados em diferentes tamanhos, enovelados e vellus, tricoptilose, pontos amarelos com ou sem pontos pretos e ausência de cabelos em "ponto de exclamação". CONCLUSÃO: No contexto de alopecia em placa e cabelos fraturados, a ausência de "pontos de exclamação" sugere o diagnóstic...
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ANÁLISE DO DIAGNÓSTICO DO DESEMPENHO EM LEITURA: PROVINHA BRASIL vs. FLUÊNCIA EM LEITURA ORAL
Directory of Open Access Journals (Sweden)
Ayane Nararela Santos Almeida
2013-01-01
Full Text Available Analisamos, por meio dos resultados obtidos na aplicação do Teste 2 da Provinha Brasil 2011 e de uma matriz de competência de fluência em leitura oral, o desempenho dos alfabetizandos na fluência em leitura oral e sua convergência com o desempenho na Provinha Brasil. Como corpus, tomamos quatro histórias sem imagens para que alunos, do 2º ano do ensino fundamental de uma escola municipal de Aracaju, fizessem a leitura oral. Durante a análise, correlacionamos a competência de fluência em leitura oral desenvolvida pelos alunos, e verificada por meio da matriz proposta neste estudo, com os resultados obtidos no Teste 2 da Provinha Brasil 2011. Concluímos que a articulação entre a matriz de competência de fluência em leitura oral em conjunto com a matriz de referência da Provinha Brasil 2011 permite contribuir significativamente para o aprimoramento da competência comunicativa e letramento do aluno alfabetizando.
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effect of neem seed husk ash em seed husk ash em seed husk ash ...
African Journals Online (AJOL)
User
scanning electron microscope (SEM) were and 25%NSHA and presented. and presented. and presented. The test results in. The test results in replacement replacement by increase in the slump at 5% and 10 increase in the slump at 5% and 10. 25% replacements. 25% replacements. At 28 days curing, only the cont.
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Directory of Open Access Journals (Sweden)
F. G. Carvalho
1999-06-01
Full Text Available Com a finalidade de avaliar a tolerância de rhizobium loti em Leucaena leucocephala cv K8, submetida a níveis crescentes de salinidade, realizou-se um experimento em casa de vegetação, usando-se um Podzólico Vermelho-Amarelo textura franco-arenosa, coletado em Serra Talhada (PE. O experimento obedeceu ao arranjo fatorial 5 x 4, no delineamento em blocos ao acaso, com 3 repetições. Foram usados 5 níveis de salinidade do solo (C.E. = 1,5; 6,6; 10,1; 12,8 e 14,4 dS m-1 e 2 tratamentos inoculados (NFB 494 e SEMIA 6069, fertilização nitrogenada com 200 mg kg-1 de N (NH4NO3, e o controle sem inoculação e sem adubação nitrogenada. O incremento dos níveis crescentes de salinidade reduziu a nodulação (número e massa de nódulos, o rendimento de matéria seca e a acumulação de N na parte aérea. O tratamento com fertilização nitrogenada inibiu totalmente a nodulação em leucena, em todos os níveis de salinidade; contudo, promoveu melhores rendimentos na acumulação de N e na produção de matéria seca. Observou-se resposta significativa das plantas inoculadas com a estirpe SEMIA 6069, em todas as características avaliadas, superando os resultados obtidos com o isolado NFB 494.
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International Nuclear Information System (INIS)
Converse, Matthew I.; Fullwood, David T.
2013-01-01
Current methods of image segmentation and reconstructions from scanning electron micrographs can be inadequate for resolving nanoscale gaps in composite materials (1–20 nm). Such information is critical to both accurate material characterizations and models of piezoresistive response. The current work proposes the use of crystallographic orientation data and machine learning for enhancing this process. It is first shown how a machine learning algorithm can be used to predict the connectivity of nanoscale grains in a Nickel nanostrand/epoxy composite. This results in 71.9% accuracy for a 2D algorithm and 62.4% accuracy in 3D. Finally, it is demonstrated how these algorithms can be used to predict the location of gaps between distinct nanostrands — gaps which would otherwise not be detected with the sole use of a scanning electron microscope. - Highlights: • A method is proposed for enhancing the segmentation/reconstruction of SEM images. • 3D crystallographic orientation data from a nickel nanocomposite is collected. • A machine learning algorithm is used to detect trends in adjacent grains. • This algorithm is then applied to predict likely regions of nanoscale gaps. • These gaps would otherwise be unresolved with the sole use of an SEM
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Scanning electron microscopy of bone.
Boyde, Alan
2012-01-01
This chapter described methods for Scanning Electron Microscopical imaging of bone and bone cells. Backscattered electron (BSE) imaging is by far the most useful in the bone field, followed by secondary electrons (SE) and the energy dispersive X-ray (EDX) analytical modes. This chapter considers preparing and imaging samples of unembedded bone having 3D detail in a 3D surface, topography-free, polished or micromilled, resin-embedded block surfaces, and resin casts of space in bone matrix. The chapter considers methods for fixation, drying, looking at undersides of bone cells, and coating. Maceration with alkaline bacterial pronase, hypochlorite, hydrogen peroxide, and sodium or potassium hydroxide to remove cells and unmineralised matrix is described in detail. Attention is given especially to methods for 3D BSE SEM imaging of bone samples and recommendations for the types of resin embedding of bone for BSE imaging are given. Correlated confocal and SEM imaging of PMMA-embedded bone requires the use of glycerol to coverslip. Cathodoluminescence (CL) mode SEM imaging is an alternative for visualising fluorescent mineralising front labels such as calcein and tetracyclines. Making spatial casts from PMMA or other resin embedded samples is an important use of this material. Correlation with other imaging means, including microradiography and microtomography is important. Shipping wet bone samples between labs is best done in glycerol. Environmental SEM (ESEM, controlled vacuum mode) is valuable in eliminating -"charging" problems which are common with complex, cancellous bone samples.
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Sender, L M; Escapa, I; Benedetti, A; Cúneo, R; Diez, J B
2018-01-01
We present the first study of cuticles and compressions of fossil leaves by Focused Ion Beam Scanning Electron Microscopy (FIB-SEM). Cavities preserved inside fossil leaf compressions corresponding to substomatal chambers have been observed for the first time and several new features were identified in the cross-section cuts. These results open a new way in the investigation of the three-dimensional structures of both micro- and nanostructural features of fossil plants. Moreover, the application of the FIB-SEM technique to both fossils and extant plant remains represent a new source of taxonomical, palaeoenvironmental and palaeoclimatic information. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.
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Directory of Open Access Journals (Sweden)
Roberto Adriana Madureira
2002-01-01
Full Text Available Introdução: a hipermobilidade articular pode estar associada à dor músculo-esquelética. A relação da hipermobilidade com a redução da densidade mineral óssea ainda é desconhecida. Existem relatos de osteoporose em associação com doenças genéticas que cursam com hipermobilidade articular. O nosso objetivo foi detectar a possível associação entre hipermobilidade articular e alterações na densidade mineral óssea (DMO em crianças com e sem dor músculo-esquelética. Casuística e métodos: foram avaliadas 93 crianças, com idade entre 5 e 10 anos, quanto à presença de hipermobilidade articular e quanto à presença de dor músculo-esquelética, através de questionário dirigido aos pais. Todas as crianças realizaram densitometria óssea de coluna lombar ao nível das vértebras L2-L4. Resultados: as crianças foram distribuídas de acordo com a presença ou não de hipermobilidade articular associada ou não à dor músculo-esquelética: 29 (31,2% com hipermobilidade e com dor músculo-esquelética, 20 (21,5% com hipermobilidade e sem dor, 22 (23,6% sem hipermobilidade e com dor e 22 (23,6% sem hipermobilidade e sem dor (grupo controle. Vinte e quatro (25,8% crianças apresentaram perda de DMO maior que 10% com relação à DMO adequada para a idade e sexo. A DMO mostrou-se significantemente menor em relação ao grupo controle nos grupos: com hipermobilidade (independente da presença de dor, com dor (independente da presença de hipermobilidade, com hipermobilidade e sem dor e sem hipermobilidade e com dor. Conclusão: a DMO pode estar diminuída em crianças com hipermobilidade (independente da presença de dor músculo-esquelética e em crianças com dor (independente da presença de hipermobilidade em relação aos controles.
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Directory of Open Access Journals (Sweden)
Mauro Carneiro de Freitas
2008-03-01
gastroesofágico de longa duração, sendo detectado em, aproximadamente, 10%-14% dos indivíduos submetidos a endoscopia digestiva alta para avaliação de sintomas relacionados à doença por refluxo gastroesofágico. Estudos de prevalência do esôfago de Barrett em indivíduos sem sintomas típicos de doença por refluxo gastroesofágico mostram taxas oscilando entre 0,6% e 25%. OBJETIVO: Determinar a prevalência do esôfago de Barrett em indivíduos maiores de 50 anos sem os sintomas clássicos da doença por refluxo gastroesofágico. MÉTODOS: Foram recrutados 104 pacientes (51 homens e 53 mulheres, idade média 65 anos, com indicação de se submeterem a endoscopia digestiva alta, porém sem sintomas de pirose e/ou regurgitação ácida (certificados através de questionário validado. Foram excluídos indivíduos com exame endoscópico prévio nos últimos 10 anos ou que fizeram uso de medicação anti-secretora nos últimos 6 meses. Durante o exame endoscópico foi realizada cromoscopia com azul de metileno, para facilitar a identificação do epitélio metaplásico. RESULTADOS: O esôfago de Barrett foi diagnosticado por endoscopia e confirmado pela histologia em quatro pacientes, todos do sexo masculino. Os segmentos metaplásicos eram curtos (inferior a 3 cm e livre de displasia em todos os pacientes. A prevalência encontrada foi de 7,75% na população masculina e 3,8% na população geral avaliada. CONCLUSÃO: Diante da baixa prevalência do esôfago de Barrett encontrada no presente estudo, associada ao achado de segmento curto de Barrett em todos os casos diagnosticados e ausência de displasia no material analisado, rastreamento endoscópico para o esôfago de Barrett em pacientes acima de 50 anos sem os sintomas clássicos da doença por refluxo gastroesofágico não se justificaria na população brasileira.
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Afasia global sem hemiparesia: relato de caso Global aphasia without hemiparesis: case report
MARCUS TULIUS TEIXEIRA DA SILVA; JOSÉ LUÍS DE SÁ CAVALCANTI; DENISE MADEIRA MOREIRA
2000-01-01
Afasia global geralmente é acompanhada por hemiparesia direita devido à extensão da lesão subjacente. Recentemente têm sido registrados na literatura casos em que tal síndrome ou não se acompanha do déficit motor ou este é apenas transitório, sendo esta condição conhecida como afasia global sem hemiparesia (AGSH). Relatamos caso de AGSH devido a infarto cerebral embólico cardiogênico, corroborando a tese de que esta condição pode ter valor preditivo para o diagnóstico de infartos embólicos.Sy...
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METHOD FOR OBSERVATION OF DEEMBEDDED SECTIONS OF FISH GONAD BY SCANNING ELECTRON MICROSCOPY
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
This article reports a method for examining the intracellular structure of fish gonads using a scanning electron microscope(SEM). The specimen preparation procedure is similar to that for transmission electron microscopy wherein samples cut into semi-thin sections are fixed and embedded in plastic. The embedment matrix was removed by solvents. Risen-free specimens could be observed by SEM. The morphology of matured sperms in the gonad was very clear, and the oocyte internal structures appeared in three-dimensional images. Spheroidal nucleoli and yolk vesicles and several bundles of filaments adhered on the nucleoli could be viewed by SEM for the first time.
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Hortolà, Policarp
2015-12-01
Some archaeological or ethnographic specimens are unavailable for direct examination using a scanning electron microscope (SEM) due to methodological obstacles or legal issues. In order to assess the feasibility of using SEM synthetic replicas for the identification of bloodstains (BSs) via morphology of red blood cells (RBCs), three fragments of different natural raw material (inorganic, stone; plant, wood; animal, shell) were smeared with peripheral human blood. Afterwards, molds and casts of the bloodstained areas were made using vinyl polysiloxane (VPS) silicone impression and polyurethane (PU) resin casting material, respectively. Then, the original samples and the resulting casts were coated with gold and examined in secondary-electron mode using a high-vacuum SEM. Results suggest that PU resin casts obtained from VPS silicone molds can preserve RBC morphology in BSs, and consequently that synthetic replicas are feasible for SEM identification of BSs on cultural heritage specimens made of natural raw materials. Although the focus of this study was on BSs, the method reported in this paper may be applicable to organic residues other than blood, as well as to the surface of other specimens when, for any reason, the original is unavailable for an SEM.
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DEFF Research Database (Denmark)
Shiraki, I.; Nagao, T.; Hasegawa, S.
2000-01-01
For in-situ measurements of surface conductivity in ultrahigh vacuum (UHV), we have installed micro-four-point probes (probe spacings down to 4 mum) in a UHV scanning electron microscope (SEM) combined with scanning reflection-high-energy electron diffraction (RHEED). With the aid of piezoactuators...
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Image contrast enhancement of Ni/YSZ anode during the slice-and-view process in FIB-SEM.
Liu, Shu-Sheng; Takayama, Akiko; Matsumura, Syo; Koyama, Michihisa
2016-03-01
Focused ion beam-scanning electron microscopy (FIB-SEM) is a widely used and easily operational equipment for three-dimensional reconstruction with flexible analysis volume. It has been using successfully and increasingly in the field of solid oxide fuel cell. However, the phase contrast of the SEM images is indistinct in many cases, which will bring difficulties to the image processing. Herein, the phase contrast of a conventional Ni/yttria stabilized zirconia anode is tuned in an FIB-SEM with In-Lens secondary electron (SE) and backscattered electron detectors. Two accessories, tungsten probe and carbon nozzle, are inserted during the observation. The former has no influence on the contrast. When the carbon nozzle is inserted, best and distinct contrast can be obtained by In-Lens SE detector. This method is novel for contrast enhancement. Phase segmentation of the image can be automatically performed. The related mechanism for different images is discussed. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.
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Analysis list: sem-4 [Chip-atlas[Archive
Lifescience Database Archive (English)
Full Text Available sem-4 Larvae + ce10 http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target/sem-4.1....tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target/sem-4.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target/sem...-4.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/colo/sem-4.Larvae.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/colo/Larvae.gml ...
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Directory of Open Access Journals (Sweden)
Rodrigo de Oliveira Mello
Full Text Available OBJETIVO: Medir a espessura das criptas e quantificar o número de células caliciformes comparando a mucosa cólica com e sem trânsito intestinal, relacionando-as ao tempo de exclusão. MÉTODOS: Sessenta ratos Wistar, foram distribuídos em três grupos com 20 animais segundo a operação final para a retirada dos cólons, realizadas em seis, 12 ou 18 semanas. Em cada grupo, 15 animais foram submetidos à derivação do trânsito por colostomia proximal no cólon esquerdo e fístula mucosa distal e cinco apenas à laparotomia (controle. Os cólons com e sem trânsito fecal foram removidos, processados, submetidos a cortes histológicos corados pela hematoxilina-eosina. A altura das criptas colônicas e o número de células caliciformes foram mensurados por morfometria computadorizada. Foram utilizados os testes t de Student e Kruskal-Wallis para comparação e análise de variância, estabelecendo-se nível de significância de 5% (p<0,05. RESULTADOS: A altura das criptas diminui nos segmentos sem trânsito fecal (p=0,0001, reduzindo entre seis e 12 semanas de exclusão (p=0,0003, estabilizando-se após este período. O número de células caliciformes nas criptas é menor nos segmentos sem trânsito após 12 e 18 semanas (p=0,0001, porém aumenta com o decorrer do tempo de exclusão (p=0,04 CONCLUSÃO: A exclusão do trânsito intestinal diminui a espessura das criptas colônicas e o número de células caliciformes nos segmentos sem trânsito. Existe aumento do número de células caliciformes com o decorrer do tempo de exclusão.
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Application of the OS-EM method to the 123I-IMP ARG method. Comparison between FBP and OS-EM methods
International Nuclear Information System (INIS)
Sasaki, Kazuko; Satou, Ayuko; Oomura, Tomomi; Ono, Madoka; Hachiya, Takenori
2004-01-01
We investigated application of the ordered subsets-expectation maximization (OS-EM) method to the 123 I-IMP autoradiography (ARG) method to measure regional cerebral blood flow (rCBF). First, scan time and subsets were fixed at 20 min and 16, respectively, and the influence of iteration on the cross calibration factor (CCF) and quantitative rCBF values obtained by the ARG method was investigated when the iteration number was set at 2, 4, 8, 16, 32, and 90. Next, with the number of iterations set at 4, we compared the scanning times of OS-EM and filtered back projection (FBP). We determined that the CCF values remained at the same level irrespective of iteration number. Quantitative rCBF values had no association with iteration number, either. Using the quantitative rCBF values obtained by 20-min. scanning with FBP as a standard, the time period for collecting SPECT data was 10 min, without sacrificing image quality or quantification. Quantitative rCBF obtained by OS-EM was estimated to be higher than that by FBP. (author)
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The Role of Scanning Electron Microscopy in the Direct Diagnosis of Onychomycosis
Directory of Open Access Journals (Sweden)
Xueping Yue
2018-01-01
Full Text Available Purpose. The purpose of this study was to evaluate the role of scanning electron microscopy (SEM in the direct diagnosis of suspected onychomycosis with negative mycological test results. Methods. Outpatients diagnosed with suspected onychomycosis with negative mycological test results, including direct microscopic examination with 10% potassium hydroxide (KOH and fungal culture, on 3 separate occasions were recruited. A small piece of infected nail was obtained for SEM examination. Results. Among the 48 suspected onychomycosis samples, SEM revealed that 18 (37.5% were positive for fungal structures, including 10 (20.8% cases of hyphae and 8 (16.7% cases of yeast blastospores or budding. Conclusion. SEM represents an effective method to diagnose suspected onychomycosis when the traditional mycological methods were negative. Therefore, this technique could be used in clinical practice.
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3D reconstruction of SEM images by use of optical photogrammetry software.
Eulitz, Mona; Reiss, Gebhard
2015-08-01
Reconstruction of the three-dimensional (3D) surface of an object to be examined is widely used for structure analysis in science and many biological questions require information about their true 3D structure. For Scanning Electron Microscopy (SEM) there has been no efficient non-destructive solution for reconstruction of the surface morphology to date. The well-known method of recording stereo pair images generates a 3D stereoscope reconstruction of a section, but not of the complete sample surface. We present a simple and non-destructive method of 3D surface reconstruction from SEM samples based on the principles of optical close range photogrammetry. In optical close range photogrammetry a series of overlapping photos is used to generate a 3D model of the surface of an object. We adapted this method to the special SEM requirements. Instead of moving a detector around the object, the object itself was rotated. A series of overlapping photos was stitched and converted into a 3D model using the software commonly used for optical photogrammetry. A rabbit kidney glomerulus was used to demonstrate the workflow of this adaption. The reconstruction produced a realistic and high-resolution 3D mesh model of the glomerular surface. The study showed that SEM micrographs are suitable for 3D reconstruction by optical photogrammetry. This new approach is a simple and useful method of 3D surface reconstruction and suitable for various applications in research and teaching. Copyright © 2015 Elsevier Inc. All rights reserved.
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Leptina e aldosterona na atividade simpática na hipertensão resistente, com ou sem Diabetes Tipo 2
Directory of Open Access Journals (Sweden)
Leandro Boer-Martins
2012-07-01
Full Text Available FUNDAMENTO: A descoberta da leptina como um estimulador da atividade simpática trouxe uma nova perspectiva para os mecanismos fisiopatológicos da obesidade-hipertensão. OBJETIVO: Avaliamos a relação entre a atividade simpática aumentada e as concentrações plasmáticas de leptina e aldosterona em Hipertensos Resistentes (HR, comparando os grupos com e sem Diabetes Tipo 2 (DT2. MÉTODOS: Vinte e cinco pacientes HR foram avaliados por eletrocardiografia ambulatorial para análise da Variabilidade da Frequência Cardíaca (VFC nos domínios do tempo e frequência, os quais foram estratificados em dois períodos: 24 horas e período Diurno (D, compreendendo as medidas entre 14 e 18h (domínio do tempo e uma hora às 15h (domínio da frequência. RESULTADOS: O grupo DT2 (n = 10 apresentou maiores concentrações de aldosterona e leptina que o grupo não DT2 (n = 15 (26,0 ± 11,5 vs. 16,9 ± 7,0 ng/dL - p = 0,021; 81,368.7 ± 47,086.1 vs. 41,228.1 ± 24,523.1 pg/mL - p = 0,048, respectivamente. Houve correlação entre aldosterona e VFC no domínio da frequência em ambos os grupos. Não-DT2 apresentaram a aldosterona correlacionada com D baixa frequência em unidades normalizadas (BFnu (r = 0,6 [0,12 - 0,85] p = 0,018 e D alta frequência em unidades normalizadas (AFnu (r = -0,6 [-0,85 - -0,12] p = 0,018. No grupo com diabetes, a aldosterona correlacionou-se com DBFnu (r = 0,72 [0,16 - 0,93] p = 0,019 e DAFnu (r = -0,72 [-0,93 - -0,16] p = 0,019. Apesar da importância da leptina na atividade simpática aumentada na hipertensão, não houve correlação com VFC. CONCLUSÃO: A aldosterona parece estimular a atividade simpática em HR com ou sem DT2. Essa informação combinada com a eficácia clínica dos bloqueadores de receptor mineralocorticoide em HR pode reforçar a aldosterona como alvo terapêutico relevantes em HR. (Arq Bras Cardiol. 2012; [online].ahead print, PP.0-0
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Fast three-dimensional nanoscale metrology in dual-beam FIB-SEM instrumentation
International Nuclear Information System (INIS)
Repetto, Luca; Buzio, Renato; Denurchis, Carlo; Firpo, Giuseppe; Piano, Emanuele; Valbusa, Ugo
2009-01-01
A quantitative surface reconstruction technique has been developed for the geometric characterization of three-dimensional structures by using a combined focused ion beam-scanning electron microscopy (FIB-SEM) instrument. A regular pattern of lines is milled at normal incidence on the sample to be characterized and an image is acquired at a large tilt angle. By analyzing the pattern under the tilted view, a quantitative estimation of surface heights is obtained. The technique has been applied to a test sample and nanoscale resolution has been achieved. The reported results are validated by a comparison with atomic force microscopy measurements.
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Charging effects of PET under electron beam irradiation in a SEM
International Nuclear Information System (INIS)
Jbara, O; Rondot, S; Hadjadj, A; Patat, J M; Fakhfakh, S; Belhaj, M
2008-01-01
This paper deals with charge trapping and charge transport of polyethylene terephthalate (PET) polymer subjected to electron irradiation in a scanning electron microscope (SEM). Measurement of displacement current and leakage current using an arrangement adapted to the SEM allows the amount of trapped charge during and after electron irradiation to be determined and the charge mechanisms regulation to be studied. These mechanisms involve several parameters related to the electronic injection, the characteristics of insulator and the effects of the trapped charge itself. The dynamic trapping properties of PET samples are investigated and the time constants of charging are evaluated for various conditions of irradiation. The determination of the trapping cross section for electrons is possible by using the trapping rate at the onset of irradiation. Many physical processes are involved in the charging and discharging mechanisms; among them surface conduction is outlined. Through the control of irradiation conditions, various types of surface discharging (flashover phenomenon) behaviour are also observed. The strength of the electric field initiating surface discharge is estimated.
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Directory of Open Access Journals (Sweden)
Alex Vieira Lima
2013-12-01
Full Text Available O objetivo deste estudo foi descrever o processo de tradução e adaptação transcultural da versão brasileira do questionário Neighborhood Environment Walkability Scale for Youth (NEWS-Y. Foram realizadas traduções independentes para o português da versão original do NEWS-Y e respectivas retrotraduções para o inglês. A análise da adaptação semântica e conceitual foi realizada por um grupo de especialistas. A versão traduzida do NEWS-Y foi aplicada em amostra de oito adolescentes de ambos os sexos e apresentou fácil compreensão. Após discretas modificações apontadas nos processos de tradução, o grupo de especialistas considerou que a versão para o idioma português do NEWS-Y apresentou equivalências semântica e conceitual. A versão traduzida do NEWS-Y necessitou de poucos ajustes para garantir a adaptação conceitual, de itens e semântica. Sugere-se que estudos complementares sejam realizados para analisar as outras etapas da adaptação transcultural da versão do NEWS-Y em português no contexto brasileiro.
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Contained scanning electron microscope facility for examining radioactive materials
International Nuclear Information System (INIS)
Hsu, C.W.
1986-03-01
At the Savannah River Laboratory (SRL) radioactive solids are characterized with a scanning electron microscope (SEM) contained in a glove box. The system includes a research-grade Cambridge S-250 SEM, a Tracor Northern TN-5500 x-ray and image analyzer, and a Microspec wavelength-dispersive x-ray analyzer. The containment facility has a glove box train for mounting and coating samples, and for housing the SEM column, x-ray detectors, and vacuum pumps. The control consoles of the instruments are located outside the glove boxes. This facility has been actively used since October 1983 for high alpha-activity materials such as plutonium metal and plutonium oxide powders. Radioactive defense waste glasses and contaminated equipment have also been examined. During this period the facility had no safety-related incidents, and personnel radiation exposures were maintained at less than 100 mrems
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Directory of Open Access Journals (Sweden)
José Sávio Bicho de Oliveira
Full Text Available Problematiza a atuação de professores que ensinam matemática em classes multisseriadas de escolas ribeirinhas da Amazônia paraense. Enfatizaram-se questões acerca do ensino-aprendizagem, no âmbito da alfabetização matemática, desenvolvidas em escolas situadas às margens ou nas proximidades dos rios da região nordeste do Pará. Os dados foram construídos com base em informações dadas por seis professores em sete escolas municipais. Os resultados identificam que a alfabetização matemática expressa no contexto ribeirinho ainda se restringe às experiências matemáticas estritamente baseadas em orientações didáticas e curriculares de âmbito global, sem levar em consideração a riqueza de possibilidades de conhecimentos sugeridas pelas experiências dos estudantes em seu contexto diário.
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Sem-edx and ftir studies of chlorinated rubber coating
International Nuclear Information System (INIS)
Bano, H.; Khan, M.I.
2013-01-01
Summary: Anticorrosive performance of chlorinated rubber coating has been investigated by visual examination, Scanning electron microscopy (SEM)/Energy dispersive X-ray (EDX) analysis and Fourier transform infrared (FTIR) spectroscopy. After surface preparation, commercially available coating system based on chlorinated rubber (primer)/chlorinated rubber (topcoat) formulation was applied on mild steel test panels (10cm x 15cm sizes). Prepared coated panels were exposed at marine, industrial and urban test sites located in Karachi, Pakistan according to ISO 8565 norm. Accelerated testing was performed by using a salt spray chamber (ASTM B117 norm). Accelerated weathering methods are the methods in which the factors responsible for the degradation of coatings are artificially intensified in order to achieve the rapid degradation of coatings. Visual examination of blistering and rusting as well as SEM micrographs indicated a more severe degradation of the coating surface characteristics at natural exposure testing sites (particularly at marine test site) than for accelerated (salt spray) testing. EDX determination of the Oxygen/Carbon (O/C) ratios also indicated increased degradation at natural test sites compared to the accelerated (salt spray) testing. Photooxidation of the binder results in the formation of carbonyl compounds as revealed by FTIR spectroscopy which also indicated dehydrochlorination. (author)
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Directory of Open Access Journals (Sweden)
Daniela Aparecida Biasotto-Gonzalez
2012-12-01
Full Text Available OBJETIVO: comparar dois ângulos cervicais com as classificações oclusais em crianças de 6 a 10 anos com e sem Disfunção Temporomandibular (DTM,identificar se há prevalência de DTM quanto ao gênero, e se há influencia da oclusão sobre os ângulos estudados. MÉTODO: realizou-se um estudo observacional transversal com 91 crianças de ambos os gêneros de uma Instituição de Ensino privado, dispostas em Grupo A (sem DTM e Grupo B (com DTM. Todas as crianças foram avaliadas seguindo uma ficha cadastral constituída de dados referentes a sexo, idade, peso, altura e exame clínico intra-oral para classificação oclusal de Angle. O diagnóstico e a severidade da DTM, foram verificados pelo questionário proposto por Fonseca. Para avaliação dos ângulos cervicais (A1 e A2 foi utilizada a fotogrametria e o Software Alcimagem®. RESULTADOS: entre as crianças avaliadas, 52 (57,14% apresentaram maloclusão, sendo 29 com DTM e 23 sem DTM, 39 (42,85% apresentaram normoclusão, sendo 18 sem DTM e 21 com DTM. Quando comparados os ângulos (A1 e A2 a classe oclusal, foi encontrada diferença significante entre as crianças normoclusivas e maloclusivas com o ângulo A1 (p=0,04. CONCLUSÃO: esse estudo demonstrou que o ângulo A1 (C7, ATM e Ápice do Mento foi estatisticamente significante quando associado com a condição oclusal. Não foi encontrado associação, na população estudada, entre ângulo cervical e DTM. Além disso, também foi possível observar que, a prevalência de crianças do gênero feminino com DTM é significantemente maior que a do gênero masculino. Esse estudo demonstrou que a maloclusão pode alterar somente o ângulo A1 e que a DTM não interfere nos ângulos cervicais estudados.PURPOSE: to compare two cervical angles with occlusal classifications in children between 6 and 10 years old with and without Temporomandibular Disorders (TMD, to identify if there is a prevalence of TMD according to gender, and if there is
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High resolution SEM imaging of gold nanoparticles in cells and tissues.
Goldstein, A; Soroka, Y; Frušić-Zlotkin, M; Popov, I; Kohen, R
2014-12-01
The growing demand of gold nanoparticles in medical applications increases the need for simple and efficient characterization methods of the interaction between the nanoparticles and biological systems. Due to its nanometre resolution, modern scanning electron microscopy (SEM) offers straightforward visualization of metallic nanoparticles down to a few nanometre size, almost without any special preparation step. However, visualization of biological materials in SEM requires complicated preparation procedure, which is typically finished by metal coating needed to decrease charging artefacts and quick radiation damage of biomaterials in the course of SEM imaging. The finest conductive metal coating available is usually composed of a few nanometre size clusters, which are almost identical to the metal nanoparticles employed in medical applications. Therefore, SEM monitoring of metal nanoparticles within cells and tissues is incompatible with the conventional preparation methods. In this work, we show that charging artefacts related to non-conductive biological specimen can be successfully eliminated by placing the uncoated biological sample on a conductive substrate. By growing the cells on glass pre-coated with a chromium layer, we were able to observe the uptake of 10 nm gold nanoparticles inside uncoated and unstained macrophages and keratinocytes cells. Imaging in back scattered electrons allowed observation of gold nanoparticles located inside the cells, while imaging in secondary electron gave information on gold nanoparticles located on the surface of the cells. By mounting a skin cross-section on an improved conductive holder, consisting of a silicon substrate coated with copper, we were able to observe penetration of gold nanoparticles of only 5 nm size through the skin barrier in an uncoated skin tissue. The described method offers a convenient modification in preparation procedure for biological samples to be analyzed in SEM. The method provides high
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SEM AutoAnalysis: enhancing photomask and NIL defect disposition and review
Schulz, Kristian; Egodage, Kokila; Tabbone, Gilles; Ehrlich, Christian; Garetto, Anthony
2017-06-01
For defect disposition and repair verification regarding printability, AIMS™ is the state of the art measurement tool in industry. With its unique capability of capturing aerial images of photomasks it is the one method that comes closest to emulating the printing behaviour of a scanner. However for nanoimprint lithography (NIL) templates aerial images cannot be applied to evaluate the success of a repair process. Hence, for NIL defect dispositioning scanning, electron microscopy (SEM) imaging is the method of choice. In addition, it has been a standard imaging method for further root cause analysis of defects and defect review on optical photomasks which enables 2D or even 3D mask profiling at high resolutions. In recent years a trend observed in mask shops has been the automation of processes that traditionally were driven by operators. This of course has brought many advantages one of which is freeing cost intensive labour from conducting repetitive and tedious work. Furthermore, it reduces variability in processes due to different operator skill and experience levels which at the end contributes to eliminating the human factor. Taking these factors into consideration, one of the software based solutions available under the FAVOR® brand to support customer needs is the aerial image evaluation software, AIMS™ AutoAnalysis (AAA). It provides fully automated analysis of AIMS™ images and runs in parallel to measurements. This is enabled by its direct connection and communication with the AIMS™tools. As one of many positive outcomes, generating automated result reports is facilitated, standardizing the mask manufacturing workflow. Today, AAA has been successfully introduced into production at multiple customers and is supporting the workflow as described above. These trends indeed have triggered the demand for similar automation with respect to SEM measurements leading to the development of SEM AutoAnalysis (SAA). It aims towards a fully automated SEM image
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3-D Analysis of Graphite Nodules in Ductile Cast Iron Using FIB-SEM
DEFF Research Database (Denmark)
D'Angelo, Luca; Jespersen, Freja N.; MacDonald, A. Nicole
Ductile cast iron samples were analysed in a Focused Ion Beam Scanning Electron Microscope, FIB-SEM. The focussed ion beam was used to carefully remove layers of the graphite nodules to reveal internal structures in the nodules. The sample preparation and milling procedure for sectioning graphite...... inside the nodules, their orientation in relation to the graphite and the chemistry of the inclusions is analysed and described. Formation of the structures during solidification and subsequent cooling to room temperature is discussed....
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Rodenburg, C.; Jepson, M. A. E.; Boden, Stuart A.; Bagnall, Darren M.
2014-06-01
Both scanning electron microscopes (SEM) and helium ion microscopes (HeIM) are based on the same principle of a charged particle beam scanning across the surface and generating secondary electrons (SEs) to form images. However, there is a pronounced difference in the energy spectra of the emitted secondary electrons emitted as result of electron or helium ion impact. We have previously presented evidence that this also translates to differences in the information depth through the analysis of dopant contrast in doped silicon structures in both SEM and HeIM. Here, it is now shown how secondary electron emission spectra (SES) and their relation to depth of origin of SE can be experimentally exploited through the use of energy filtering (EF) in low voltage SEM (LV-SEM) to access bulk information from surfaces covered by damage or contamination layers. From the current understanding of the SES in HeIM it is not expected that EF will be as effective in HeIM but an alternative that can be used for some materials to access bulk information is presented.
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Does your SEM really tell the truth? How would you know? Part 2.
Postek, Michael T; Vladár, András E; Purushotham, Kavuri P
2014-01-01
The scanning electron microscope (SEM) has gone through a tremendous evolution to become indispensable for many and diverse scientific and industrial applications. The improvements have significantly enriched and augmented the overall SEM performance and have made the instrument far easier to operate. But, the ease of operation also might lead, through operator complacency, to poor results. In addition, the user friendliness has seemingly reduced the need for thorough operator training for using these complex instruments. One might then conclude that the SEM is just a very expensive digital camera or another peripheral device for a computer. Hence, a person using the instrument may be lulled into thinking that all of the potential pitfalls have been eliminated and they believe everything they see on the micrograph is always correct. But, this may not be the case. An earlier paper (Part 1), discussed some of the potential issues related to signal generation in the SEM, instrument calibration, electron beam interactions and the need for physics-based modeling to understand the actual image formation mechanisms. All these were summed together in a discussion of how these issues effect measurements made with the instrument. This second paper discusses another major issue confronting the microscopist: electron-beam-induced specimen contamination. Over the years, NIST has done a great deal of research into the issue of sample contamination and its removal and elimination and some of this work is reviewed and discussed here. © 2013 Wiley Periodicals, Inc.
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Determination of gel content and SEM morphology for sago-PVA blends film
International Nuclear Information System (INIS)
Sarada Idris; Zulkafli Ghazali; Kamarudin Hashim
2006-01-01
Blends of polyvinyl alcohol and sago starch have been prepared to evaluate the potential of producing biodegradable products. Glycerol was introduced in the blends to improve the flexibility of the films as plasticizer in order more flexible film. These blends have been subjected to electron beam irradiation to evaluate and characterized radiation effect on the blends. Subsequently films were produced from this blend. The gel content of un-irradiated and irradiated films as evidence of cross linking was measured and discussed. This paper also discuss the films morphology from Scanning Electron Microscopy(SEM) observation. (Author)
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3D SEM for surface topography quantification – a case study on dental surfaces
International Nuclear Information System (INIS)
Glon, F; Flys, O; Lööf, P-J; Rosén, B-G
2014-01-01
3D analysis of surface topography is becoming a more used tool for industry and research. New ISO standards are being launched to assist in quantifying engineering surfaces. The traditional optical measuring instrumentation used for 3D surface characterization has been optical interferometers and confocal based instrumentation. However, the resolution here is limited in the lateral dimension to the wavelength of visible light to about 500 nm. The great advantage using the SEM for topography measurements is the high flexibility to zoom from low magnifications and locating interesting areas to high magnification of down to nanometer large surface features within seconds. This paper presents surface characterization of dental implant micro topography. 3D topography data was created from SEM images using commercial photogrammetric software. A coherence scanning interferometer was used for reference measurements to compare with the 3D SEM measurements on relocated areas. As a result of this study, measurements emphasizes that the correlation between the accepted CSI measurements and the new technology represented by photogrammetry based on SEM images for many areal characterization parameters are around or less than 20%. The importance of selecting sampling and parameter sensitivity to varying sampling is high-lighted. Future work includes a broader study of limitations of the photogrammetry technique on certified micro-geometries and more application surfaces at different scales
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Directory of Open Access Journals (Sweden)
Marcelo Moraes Valença
2002-09-01
Full Text Available A retrospective study was performed in order to evaluate the frequency of abnormalities found by computed tomography (CT scan of the head in 78 patients with migraine or tension-type headache. In the present study CT scan was normal in 61.5% of the patients with migraine or tension-type headache. A number of abnormalities were encountered in more than one third of the patients studied, including inflammatory sinus disease (19.2%, cysticercosis (3.9%, unruptuted cerebral aneurysm (2.6%, basilar impression (2.6%, intracranial lipoma (2.6%, arachnoid cyst (2.6%, empty sella (2.6%, intracranial neoplasm (2.6%, and others (2.6%. None of these lesions were symptomatic or responsible by the headache picture, therefore, considered incidental findings. In conclusion, the fortuitous encounter of some abnormalities on CT scan of the head is often higher than what we could predict in patients suffering migraine or tension-type headache. We briefly discuss clinical, epidemiologic, and practical management of some of the abnormalities detected by CT scan as well as the indication to request a neuroimaging investigation.Um estudo retrospectivo foi realizado visando avaliar a frequência de anormalidades encontradas durante a realização de estudo por tomografia computadorizada (TC em 78 pacientes com migrânea ou cefaléia do tipo tensional. A TC foi normal em 61,5% dos pacientes examinados. Em um terço dos pacientes estudados foram detectadas anormalidades, como doença inflamatória dos seios paranasais (19,2%, cisticercose (3,9%, aneurisma cerebral não-roto (2,6%, impressão basilar (2,6%, lipoma intracraniano (2,6%, cisto aracnoideo (2,6%, sela vazia (2,6%, neoplasia intracraniana (2,6% e outras afecções (2,6%. Nenhuma destas lesões era sintomática (achado incidental. Concluindo, o encontro fortuito de algumas anormalidades na TC é frequentemente mais elevado do que se prediz em pacientes com cefaléia primária. Nós discutimos brevemente alguns
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Super-resolution for asymmetric resolution of FIB-SEM 3D imaging using AI with deep learning.
Hagita, Katsumi; Higuchi, Takeshi; Jinnai, Hiroshi
2018-04-12
Scanning electron microscopy equipped with a focused ion beam (FIB-SEM) is a promising three-dimensional (3D) imaging technique for nano- and meso-scale morphologies. In FIB-SEM, the specimen surface is stripped by an ion beam and imaged by an SEM installed orthogonally to the FIB. The lateral resolution is governed by the SEM, while the depth resolution, i.e., the FIB milling direction, is determined by the thickness of the stripped thin layer. In most cases, the lateral resolution is superior to the depth resolution; hence, asymmetric resolution is generated in the 3D image. Here, we propose a new approach based on an image-processing or deep-learning-based method for super-resolution of 3D images with such asymmetric resolution, so as to restore the depth resolution to achieve symmetric resolution. The deep-learning-based method learns from high-resolution sub-images obtained via SEM and recovers low-resolution sub-images parallel to the FIB milling direction. The 3D morphologies of polymeric nano-composites are used as test images, which are subjected to the deep-learning-based method as well as conventional methods. We find that the former yields superior restoration, particularly as the asymmetric resolution is increased. Our super-resolution approach for images having asymmetric resolution enables observation time reduction.
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Haj-Daoud, A.; Katscher, U.; Bein, B. K.; Pelzl, J.; Bach, H.; Oswald, W.
1999-03-01
A seal which had been in contact with sea water of high salt concentration, has been analysed, in order to characterize the erosion effects and throw light on the erosion mechanisms. The measured effective thermal depth profiles have been interpreted phenomenologically and have been correlated with energy-dispersive X-ray microanalysis (EDX) and scanning electron microscopy (SEM).
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Experiências de abortos provocados em clínicas privadas no Nordeste brasileiro
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Paloma Silveira
Full Text Available Resumo Baseado numa investigação qualitativa desenvolvida em 2012, o artigo analisa experiências de abortos provocados de pessoas de estratos sociais médios realizados em clínicas privadas. Foram narradas 34 histórias de gravidezes interrompidas em clínicas por 19 mulheres e cinco homens, residentes em duas capitais do Nordeste brasileiro. Uma análise temática revela que existem diferentes tipos de clínicas e de atendimento prestados pelos médicos. O artigo mostra que a realização de um aborto em uma clínica privada não é garantia de um atendimento humanizado e seguro. As narrativas fornecem descrições de diversas situações e práticas, desde aquelas com algumas falhas, como a falta de informações sobre os medicamentos, até outras com abusos graves, como procedimentos realizados sem anestesia. Assim, conclui-se que a ilegalidade da prática do aborto, no Brasil, permite que as clínicas funcionem sem qualquer tipo de regulação do Estado, não impedindo que as mulheres realizem abortos, mas as expondo a situações de total vulnerabilidade e de violação dos direitos humanos.
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Experiências de abortos provocados em clínicas privadas no Nordeste brasileiro
Directory of Open Access Journals (Sweden)
Paloma Silveira
2016-01-01
Full Text Available Resumo Baseado numa investigação qualitativa desenvolvida em 2012, o artigo analisa experiências de abortos provocados de pessoas de estratos sociais médios realizados em clínicas privadas. Foram narradas 34 histórias de gravidezes interrompidas em clínicas por 19 mulheres e cinco homens, residentes em duas capitais do Nordeste brasileiro. Uma análise temática revela que existem diferentes tipos de clínicas e de atendimento prestados pelos médicos. O artigo mostra que a realização de um aborto em uma clínica privada não é garantia de um atendimento humanizado e seguro. As narrativas fornecem descrições de diversas situações e práticas, desde aquelas com algumas falhas, como a falta de informações sobre os medicamentos, até outras com abusos graves, como procedimentos realizados sem anestesia. Assim, conclui-se que a ilegalidade da prática do aborto, no Brasil, permite que as clínicas funcionem sem qualquer tipo de regulação do Estado, não impedindo que as mulheres realizem abortos, mas as expondo a situações de total vulnerabilidade e de violação dos direitos humanos.
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FIB/SEM and SEM/EDS microstructural analysis of metal-ceramic and zirconia-ceramic interfaces.
Massimi, F; Merlati, G; Sebastiani, M; Battaini, P; Menghini, P; Bemporad, E
2012-01-10
Recently introduced FIB/SEM analysis in microscopy seems to provide a high-resolution characterization of the samples by 3D (FIB) cross-sectioning and (SEM) high resolution imaging. The aim of this study was to apply the FIB/SEM and SEM/EDS analysis to the interfaces of a metal-ceramic vs. two zirconia-ceramic systems. Plate samples of three different prosthetic systems were prepared in the dental lab following the manufacturers' instructions, where metal-ceramic was the result of a ceramic veneering (porcelain-fused-to-metal) and the two zirconia-ceramic systems were produced by the dedicated CAD-CAM procedures of the zirconia cores (both with final sintering) and then veneered by layered or heat pressed ceramics. In a FIB/SEM equipment (also called DualBeam), a thin layer of platinum (1 μm) was deposited on samples surface crossing the interfaces, in order to protect them during milling. Then, increasingly deeper trenches were milled by a focused ion beam, first using a relatively higher and later using a lower ion current (from 9 nA to 0.28 nA, 30KV). Finally, FEG-SEM (5KV) micrographs (1000-50,000X) were acquired. In a SEM the analysis of the morphology and internal microstructure was performed by 13KV secondary and backscattered electrons signals (in all the samples). The compositional maps were then performed by EDS probe only in the metal-ceramic system (20kV). Despite the presence of many voids in all the ceramic layers, it was possible to identify: (1) the grain structures of the metallic and zirconia substrates, (2) the thin oxide layer at the metal-ceramic interface and its interactions with the first ceramic layer (wash technique), (3) the roughness of the two different zirconia cores and their interactions with the ceramic interface, where the presence of zirconia grains in the ceramic layer was reported in two system possibly due to sandblasting before ceramic firing.
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Efetividade do Programa de Fisioterapia Aquática na amplitude de movimento em idosas
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Eduardo Aguilar Arca
2014-03-01
Full Text Available O objetivo deste estudo foi verificar os efeitos de um programa de fisioterapia aquática na amplitude de movimento em mulheres idosas. Estudo quase-experimental, sem grupo-controle, com 16 idosas, avaliadas em três momentos da intervenção. Verificou-se que o programa de fisioterapia aquática produziu efeitos expressivos no ganho da amplitude de movimento em todas as articulações e eixos de movimentos estudados, além do engajamento de pessoas idosas em atividades físicas importante para essa fase da vida.
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Blocos semânticos: o movimento argumentativo na construção do sentido no discurso
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Ernani Cesar de FREITAS
2008-07-01
Full Text Available Este trabalho tem por objetivo sistematizar e aplicar conceitos da Semântica Argumentativa de Oswald Ducrot e Marion Carel, no que diz respeito ao modelo teórico dos Blocos Semânticos, de modo que dêem conta da construção do sentido de unidades mais complexas como o texto e o discurso. A tese concebida como norteadora deste estudo, seguindo a metodologia proposta por Ducrot (1987, pressupõe que o texto é um bloco semântico inscrito no nível teórico da produção e realizado pelo encadeamento argumentativo complexo que é o discurso, orientado argumentativamente pelo uso de conectores tipo DC e/ ou PT. As análises discursivas realizadas, neste trabalho, demonstram que os encadeamentos dos enunciados estão bem marcados pelos conectores donc e pourtant que dão sentido ao discurso complexo, pelas conexões semânticas produzidas em suas AI e AE. Esse movimento argumentativo resulta da interdependência dos segmentos argumentativos, dos encadeamentos e por conseqüência dos blocos semânticos, todos interconectados e interdependentes nas relações de sentido que estabelecem entre si, processo que culmina na realização linguística de nível complexo constituído pelo texto, entidade abstrata subjacente aos discursos realizados, e pelo discurso, como seqüência de enunciados interligados, por isso, também entendido como entidade concreta, ou seja, a manifestação e realização do texto.
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Blocos semânticos: o movimento argumentativo na construção do sentido no discurso
Directory of Open Access Journals (Sweden)
Ernani Cesar de FREITAS
2013-10-01
Full Text Available Este trabalho tem por objetivo sistematizar e aplicar conceitos da Semântica Argumentativa de Oswald Ducrot e Marion Carel, no que diz respeito ao modelo teórico dos Blocos Semânticos, de modo que dêem conta da construção do sentido de unidades mais complexas como o texto e o discurso. A tese concebida como norteadora deste estudo, seguindo a metodologia proposta por Ducrot (1987, pressupõe que o texto é um bloco semântico inscrito no nível teórico da produção e realizado pelo encadeamento argumentativo complexo que é o discurso, orientado argumentativamente pelo uso de conectores tipo DC e/ ou PT. As análises discursivas realizadas, neste trabalho, demonstram que os encadeamentos dos enunciados estão bem marcados pelos conectores donc e pourtant que dão sentido ao discurso complexo, pelas conexões semânticas produzidas em suas AI e AE. Esse movimento argumentativo resulta da interdependência dos segmentos argumentativos, dos encadeamentos e por conseqüência dos blocos semânticos, todos interconectados e interdependentes nas relações de sentido que estabelecem entre si, processo que culmina na realização linguística de nível complexo constituído pelo texto, entidade abstrata subjacente aos discursos realizados, e pelo discurso, como seqüência de enunciados interligados, por isso, também entendido como entidade concreta, ou seja, a manifestação e realização do texto.
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Soares, Luís Eduardo Silva; Soares, Ana Lúcia Silva; De Oliveira, Rodrigo; Nahórny, Sidnei
2016-07-01
FT-Raman spectroscopy and scanning electron microscopy (SEM) were employed to test the hypothesis that the beverage consumption or mouthwash utilization would change the chemistry of dental materials and enamel inorganic content. Bovine enamel samples (n = 36) each received two cavity preparations (n = 72), each pair filled with one of three dental materials (R: nanofilled composite resin, GIC: glass-ionomer cement, RMGIC: resin-modified GIC). Furthermore, they were treated with three different solutions (S: artificial saliva, E: erosion/Pepsi Twist or EM: erosion + mouthwash/Colgate Plax). Reduction of carbonate content of enamel was greater in RE than RS (P erosion. Material degradation was greater after E and EM than S. GIC and RMGIC materials had a positive effect against acid erosion in the adjacent enamel after remineralization with mouthwash. The beverage and mouthwash utilization would change R and GIC chemical properties. A professional should periodically monitor the glass-ionomer and resin restorations, as they degrade over time under erosive challenges and mouthwash utilization. Microsc. Res. Tech., 2016. © 2016 Wiley Periodicals, Inc. Microsc. Res. Tech. 79:646-656, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
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Scanning electron microscopy of cells from periapical lesions.
Farber, P A
1975-09-01
Examination of lymphocytes from peripheral blood with the scanning electron microscope (SEM) has shown differences between B cells and T cells on the basis of their surface architecture. This study was initiated to determine whether the cellular components of periapical lesions could be identified with the use of similar criteria. Cells were dispersed from lesions by aspiration of fragments of tissue through syringe needles of decreasing diameters. The liberated cells were filtered on silver-coated Flotronic membranes and examined under the SEM. Lymphocytes, macrophages, epithelial cells, and mast cells were observed in granulomas and cysts. Most of the lymphocytes had smooth surfaces similar to that of T cells; others had villous projections similar to that of B cells. Epithelial nests were seen in the cyst linings while the cyst fluid was rich in lymphocytes. These findings suggest that SEM examination of periapical lesions can be a useful adjunct in studying cellular composition and possible immunological reactions in these tissues.
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Directory of Open Access Journals (Sweden)
M.I.P. Palumbo
2013-06-01
Full Text Available O objetivo deste trabalho foi realizar estudo normativo dos potenciais evocados auditivos obtidos de 34 cães sem raça definida e avaliar a influência da idade nos resultados obtidos. Os animais foram divididos em dois grupos de diferentes faixas etárias e o potencial evocado auditivo foi realizado com um estímulo de 85dB. O grupo 1 incluiu 16 cães com idades entre um e oito anos e o grupo 2, 18 animais com idades acima de oito anos. O comprimento e o diâmetro da cabeça foram mensurados e não houve diferença estatística entre os dois grupos. No grupo 1, as médias das latências das ondas I, III e V foram: 1,13; 2,64 e 3,45ms; e dos intervalos I-III, III-V e I-V foram 1,51; 0,81 e 2,32ms, respectivamente. No grupo 2, as médias das latências das ondas I, III e V foram 1,15; 2,62 e 3,55ms; e dos intervalos I-III, III-V e I-V foram 1,47; 0,93 e 2,40ms, respectivamente. As latências observadas neste estudo foram semelhantes a estudos prévios realizados por outros autores. Nos grupos etários analisados e nas condições preestabelecidas deste estudo, a idade influenciou a latência da onda V e, consequentemente, modificou os intervalos III-V e I-V, portanto deve-se considerar essa variante na interpretação dos resultados do BAEP em cães.
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Contact detection for nanomanipulation in a scanning electron microscope
International Nuclear Information System (INIS)
Ru, Changhai; To, Steve
2012-01-01
Nanomanipulation systems require accurate knowledge of the end-effector position in all three spatial coordinates, XYZ, for reliable manipulation of nanostructures. Although the images acquired by a scanning electron microscope (SEM) provide high resolution XY information, the lack of depth information in the Z-direction makes 3D nanomanipulation time-consuming. Existing approaches for contact detection of end-effectors inside SEM typically utilize fragile touch sensors that are difficult to integrate into a nanomanipulation system. This paper presents a method for determining the contact between an end-effector and a target surface during nanomanipulation inside SEM, purely based on the processing of SEM images. A depth-from-focus method is used in the fast approach of the end-effector to the substrate, followed by fine contact detection. Experimental results demonstrate that the contact detection approach is capable of achieving an accuracy of 21.5 nm at 50,000× magnification while inducing little end-effector damage. -- Highlights: ► We presents a simple method for obtaining the depth information in SEM-based nanomanipulation. ► Detecting contact between an end-effector and a target surface using SEM as a vision sensor. ► Additional touch/force sensors or specialized hardware need not be added. ► Achieved high repeatability and accuracy. ► Complete automatic contact detection within typically 60 s.
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Abreu,Paulo Giovanni de; Baêta,Fernando da Costa; Abreu,Valéria Maria Nascimento; Soares,Paulo Rubens; Perdomo,Carlos Cláudio; Silva,Martinho de Almeida e
2000-01-01
RESUMO - Este experimento foi realizado em duas fases para estudar o efeito de diferentes sistemas de aquecimento em piso sobre os desempenhos produtivo e bioeconômico de frangos de corte. Um total de 500 pintos de um dia, 50% macho e 50% fêmea, em cada círculo de proteção, foi distribuído em um delineamento experimental em blocos casualizados, com sete tratamentos e quatro blocos. Os sistemas de aquecimento testados foram: placa de fibra de vidro sem cobertura de lona plástica; placa de fibr...
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Directory of Open Access Journals (Sweden)
Alexandre Coletto-Silva
2005-09-01
Full Text Available No Brasil a criação racional de abelhas sem ferrão é denominada meliponicultura. As abelhas sem ferrão possuem diferentes comportamentos de nidificação, com ninhos internos (cavidades naturais ou não e externos. Um dos principais problemas apresentados na meliponicultura é a captura de uma colônia com o objetivo de iniciar um meliponário sem "destruir as árvores" ou mesmo as próprias colônias durante a captura. O presente trabalho apresenta um método alternativo para captura de colônias de abelhas sem ferrão, especialmente, do gênero Melipona Illiger, 1806, que são as espécies mais utilizadas para produção de mel e pólen, na região Amazônica. O método consiste em abrir uma janela na árvore, coletar o material e fechar a abertura utilizando a resina vegetal conhecida como breu.Meliponiculture is the name for stingless beekeeping in Brazil. Stingless bees have different nest behaviors showing external and internal nests (natural cavities or not. One of the main problems of meliponiculture is the capture of a colony in order to begin a meliponary without destroying trees or the colonies during the capture. A new alternative method for the capture of stingless bee colonies is presented for the genus Melipona Illiger, 1806, which are the species mostly used for producing honey and pollen. The method is to open the tree, collect the colony, and then close the tree with natural resins known as "breu".
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Aplicação de cobertura de quitosana em jabuticabas
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Estéfani Silva
2017-12-01
Full Text Available A jabuticabeira é uma frutífera nativa do Brasil, que possui frutos com período de utilização bastante reduzido devido a sua alta perecibilidade. Além disso, a jabuticaba é um fruto que contem grande valor nutricional, apresentando em sua composição alto teor de antocianinas, pigmentos naturais solúveis em água. Visando o aumento do vida de útil deste fruto aplicou-se cobertura comestível a base de quitosana, formando barreira contra gases e proporcionando ação antifúngica. As coberturas foram preparadas com quitosana, cloreto de cálcio, água destilada e acidificadas com acido lático. As jabuticabas foram imersas em solução de cobertura, secas e armazenadas sob temperatura de refrigeração por 360 horas. Durante a armazenagem foram avaliadas, a cada 72h em triplicata, quanto a perda de massa, teor de sólidos solúveis, teor de antocianinas, acidez, pH e cor. Os sólidos solúveis, pH e acidez titulável não alcançaram diferença significativa entre os frutos com a cobertura de quitosana e sem a mesma para a extensão da vida útil.A perda de massa em 288horas teve uma diferença de 0,45% em relação as frutas sem cobertura.Em relação a cor, os frutos ficaram na faixa de cor violeta. Os frutos com cobertura apresentaram maior saturaçãoe se tornaram mais escura devido a queda nos índices de luminosidade. Quanto ao teor de antocianinas houve uma redução de 24,61% a menos que os frutos que não receberam a cobertura de quitosana.
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Lithothamnium calcareum no tratamento de osteotomia experimental em coelhos (Oryctolagus cuniculus
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N.S. Ucrós
2012-06-01
Full Text Available Avaliaram-se os efeitos da suplementação com Lithothamnium calcareum na consolidação de osteotomia experimental em coelhos, por meio de exames radiográfico e histológico. Utilizaram-se 10 coelhos machos da raça Nova Zelândia, de quatro a cinco meses de idade, com massa corporal média de 2,5kg, os quais foram submetidos à osteotomia do terço médio da tíbia direita e à fixação interna com dois pinos intramedulares. Os coelhos foram distribuídos aleatoriamente em dois grupos experimentais (A e B com cinco animais cada. O grupo A recebeu diariamente dieta contendo 0,75% de L. calcareum, e o grupo B constituiu o controle sem tratamento adicional à fixação da osteotomia. A evolução clínica ocorreu sem intercorrências. As radiografias foram realizadas antes do estudo e em intervalos de 15 dias até o final do experimento, e a histologia foi realizada aos 60 dias. As avaliações radiográficas permitiram acompanhar a evolução do processo de consolidação que ocorreu em todos os casos. Histologicamente, verificou-se consolidação completa em todos os animais do grupo B (controle e em 75% do grupo A. Dos resultados pode-se concluir que, embora tenha ocorrido a consolidação clínica e a radiográfica aos 60 dias em todos os casos, histologicamente o grupo-controle (B foi melhor, mostrando que o organismo sadio não necessita de estímulo para o processo de reparação óssea. Novas pesquisas devem ser realizadas para avaliar o efeito da suplementação mineral em animais portadores de deficiências nutricionais.
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Observation of diamond turned OFHC copper using Scanning Tunneling Microscopy
Energy Technology Data Exchange (ETDEWEB)
Grigg, D.A.; Russell, P.E.; Dow, T.A.
1988-12-01
Diamond turned OFHC copper samples have been observed within the past few months using the Scanning Tunneling Microscope. Initial results have shown evidence of artifacts which may be used to better understand the diamond turning process. The STM`s high resolution capability and three dimensional data representation allows observation and study of surface features unobtainable with conventional profilometry systems. Also, the STM offers a better quantitative means by which to analyze surface structures than the SEM. This paper discusses findings on several diamond turned OFHC copper samples having different cutting conditions. Each sample has been cross referenced using STM and SEM.
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Priorização do transporte publico em intersecções semaforizadas
Nicolau Pizzolante Neto
2003-01-01
Resumo: O ônibus, principal meio de transporte de passageiros nas áreas urbanas brasileiras, recebe, em geral, tratamento idêntico aos veículos de pequeno porte em meio ao trânsito. Exceções, como faixas exclusivas e outras providências, geralmente em vias arteriais, ocupam leitos carroçáveis sem otimizar seu uso, criando áreas, que deixam, desnecessariamente, de atender a demandas de fluxo. Pode-se priorizar a passagem dos ônibus e adequar para isso o uso da via. O presente estudo vem ao enc...
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The application of SEM in analyzing the damage to the petroleum reservoirs caused by drilling fluids
International Nuclear Information System (INIS)
Abdul Razak Ismail
1996-01-01
An experimental study has been conducted to analyze the damage to the potential oil and gas reservoirs due to the invasion of drilling fluid during drilling operation. Two types of rock samples representing low and high permeability were used to stimulate the petroleum reservoirs. Sea water based drilling fluids were used in this study. Detail observations to the rock samples were analyzed using scanning electron microscope (SEM). The results of both permeability restoration and SEM observation showed that severe permeability impairments were obtained for high permeability rock. These results indicate that the relative size of the barite particles and the pore size distribution and characteristics of the formation play an important role in determining the damage caused by the drilling fluids
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Leonardo Moscovici
2013-01-01
Objetivos: Estudar a confiabilidade e validade de uma versão brasileira dos módulos Episódio Depressivo Maior (EDM) e Transtorno de Ansiedade Generalizado (TAG) do Mini International Neuropsychiatric Interview TRACKING (MINI-TRACKING); comparar a evolução de pacientes com diagnóstico de EDM e TAG seguidos por equipes de Estratégia de Saúde da Família (ESF) com acesso ao modelo de Cuidado Colaborativo (CC) em Saúde Mental versus um grupo de pacientes seguidos por equipes sem acesso ao CC. Met...
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Marketing interno e cultura organizacional: um estudo de caso em empresa de multi marcas.
Directory of Open Access Journals (Sweden)
Antonio Carlos Giuliani
2005-04-01
Full Text Available Não há planejamento que sobreviva, dentro das organizações, a um organismo social sem espírito de equipe, iniciativa, ou atuando sem a definição de valores por seus dirigentes. Em suma, sem diretrizes que componham a sua cultura organizacional. A análise da cultura organizacional permite a identificação de disfunção nos fatores culturais que estão interferindo no clima organizacional e, por conseqüência, no relacionamento entre as pessoas, prejudicando sua produtividade e o bom andamento dos trabalhos. Este estudo objetivou examinar a contribuição da cultura organizacional ao desenvolvimento de programas de marketing interno, filosofia empresarial da área de marketing, buscando o comprometimento dos funcionários com as metas da organização. Como referencial da prática, baseou-se em estudo de caso realizado na Comercial Importadora Ltda., empresa de multimarcas, com 35 funcionários, localizada em Piracicaba – São Paulo. Como resultados, o estudo possibilitou uma análise de como a cultura organizacional contribui para o uso de técnicas de marketing interno, mostrando a aplicabilidade prática dos dois conceitos.
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International Nuclear Information System (INIS)
Callaway, W.S.
1995-09-01
This is Fiscal Year 1995 Annual Report on the progress of activities relating to the application of scanning electron microscopy in addressing the Ferrocyanide Safety Issue associated with Hanford Site high-level radioactive waste tanks. The status of the FY 1995 activities directed towards establishing facilities capable of providing SEM based micro-characterization of ferrocyanide tank wastes is described. A summary of key events in the SEM task over FY 1995 and target activities in FY 1996 are presented. A brief overview of the potential applications of computer controlled SEM analytical data in light of analyses of ferrocyanide simulants performed by an independent contractor is also presented
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Directory of Open Access Journals (Sweden)
Wilson Takashi Hida
2009-08-01
monofocal. A avaliação oftalmológica contou com medida da acuidade visual para longe, intermediária e curta distância, sem correção e com a melhor correção óptica, teste de sensibilidade ao contraste e análise de frente de onda por meio do aberrômetro OPD-Scan. RESULTADOS: As aberração total e aberração esférica no grupo multifocal foi estatisticamente inferior comparada com o grupo monofocal. No grupo monofocal 75% apresentaram acuidade visual monocular intermediária sem correção entre Jaeger 1 e 6, no grupo multifocal 75% apresentaram mais que Jaeger 6. Aproximadamente 87,5% do grupo multifocal e 6,3% do grupo monofocal apresentaram acuidade visual monocular sem correção para perto de 20/30 (J2, N5, ou melhor, e 90,0% dos olhos do grupo multifocal e 37,5% do grupo monofocal apresentaram acuidade visual monocular sem correção para perto de 20/40 (J3, N6 ou melhor. A média de erro esférico foi de 0,11 D no grupo multifocal e -0,18 D no grupo monofocal (p=0,0379. O grupo monofocal apresentou superioridade estatística na sensibilidade ao contraste em condições fotópicas (p=0,014 e mesópicas (p=0,0044 a 6 cpg quando comparada ao grupo multifocal. CONCLUSÃO: A lente intraocular multifocal apresentou menos aberração esférica comparada à lente intraocular monofocal, da prevista multifocalidade sem correção para longe e perto. Entretanto, o grupo multifocal apresentou baixa sensibilidade ao contraste.
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SEM-EDX--a useful tool for forensic examinations
International Nuclear Information System (INIS)
Zadora, G.; Brozek-Mucha, Z.
2003-01-01
There are two main aims of forensic examination of the physical evidences. The first aim is comparison of the evidence with the reference material (called discrimination). The task is to find out whether they could have come from the same object. The second aim, when there is no comparative material available, is a classification of the evidence sample into a group of objects taking into account its specific chemical and physical properties. Scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDX) is a powerful tool for forensic scientists to classify and discriminate evidence material because they can simultaneously examine the morphology and the elemental composition of objects. Moreover, the obtained results could be enhanced using some methods of chemometric analysis. A few examples of problems related to the classification and discrimination of selected types of microtraces are presented
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Directory of Open Access Journals (Sweden)
Hans-Jürgen Kestenbach
1997-03-01
Full Text Available RESUMO: Trabalhando com elétrons de baixa energia (na faixa de 1keV, o novo microscópio eletrônico de varredura dispensa a etapa de metalização e permite a observação direta da estrutura lamelar de polímeros semicristalinos, sem a necessidade de preparação de amostras. São apresentados exemplos da morfologia lamelar do PVDF em função das condições de processamento e da temperatura de cristalização, em filmes contendo as fases a, b e g. Um outro exemplo revela o crescimento inicial da camada transcristalina que se formou ao longo de uma fibra de polietileno de ultra-alto peso molecular embutida em matriz de polietileno de alta densidade.ABSTRACT: Working with low energy electrons (in the range of 1keV, the new scanning electron microscope permits the lamellar (supermolecular structure of semicrystalline polymers to be observed directly without the need of specimen coating or of any other sample preparation technique. Microscope performance is demonstrated by several examples of high resolution micrographs which show spherulitic, lamellar and fibrilar morphologies developed by the a, b and g phases of PVDF as a function of processing conditions and crystallization temperature. Another example reveals the early stages of transcrystalline layer formation in HDPE reinforced by UHMWPE fibers.
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Directory of Open Access Journals (Sweden)
Renzo Freire de Almeida
2007-08-01
Full Text Available O presente estudo foi desenvolvido com o objetivo de avaliar o metabolismo do ferro por meio da determinação do eritrograma, contagem de reticulócitos, dosagem de ferro sérico, ferritina sérica e transferrina sérica de suínos em fase de terminação alimentados com dietas contendo fitase, sem suplemento micromineral/vitamínico e redução dos níveis de fósforo inorgânico (Pi. Foram utilizadas 48 fêmeas suínas de linhagem comercial, com peso inicial de 60kg, distribuídas em seis tratamentos com oito animais em cada grupo. A colheita de sangue foi feita em um grupo de 24 animais com 100kg e em outro grupo de 24 animais com 120kg. Não foram observadas diferenças (P>0,05 nos valores obtidos do eritrograma, da contagem de reticulócitos, de ferro sérico e de transferrina para os animais nos tratamentos testados. Com relação à ferritina, verificou-se que os animais até os 100kg de peso vivo que receberam ração sem suplemento micromineral/vitamínico, sem fósforo inorgânico e com fitase apresentaram valores superiores (PThis research was aimed at evaluating the effect of mineral-vitamin supplement withdrawal associated to reduction of inorganic phosphorus level and addition of phytase in feed on iron metabolism of finishing-phase pigs. Erythrocyte and reticulocyte count, serum iron, ferritin and transferrin quantification was performed. Forty eight hybrid swine females with initial average weight of 60kg were allotted to a completely randomized experimental design with six with four replications of two animals each. Blood was drawn from a group of twenty four 100kg animals and from a second group of twenty four 120kg animals. No differences (P>0.05 were observed in erythrocyte and reticulocyte count or serum iron and transferrin quantification. However, ferritin levels were increased in 100kg animals fed basal feed without mineral/vitamin supplement and inorganic phosphorus with phytase when compared to animals fed basal feed
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Energy Technology Data Exchange (ETDEWEB)
Barba de la Rosa, A.P.; Paredes-Lopez, O.; Carabez-Trejo, A.; Ordorica-Falomir, C. (Instituto Politecnico Nacional, Irapuato (Mexico). Centro de Investigacion y de Estudios Avanzados)
1989-11-01
High-protein amaranth flour (HPAF) and carbohydrate rich fraction (CRF) were produced from raw flour in a single-step process using a heat-stable alpha-amylase preparation. Protein content of flour increased from 15 to about 30 or 39% at liquefaction temperatures of 70 or 90{sup 0}C, respectively and 30 min hydrolysis time. CRF exhibited 14-22 DE. Enzymatic action at 70{sup 0}C increased endotherm temperature and gelatinization enthalpy of HPAF, in relation to gelatinized flour, as assessed by differential scanning calorimetry (DSC). Hydrolysis at 90{sup 0}C did not affect significantly (P > 0.05) DSC peak temperature. It is suggested that these changes in DSC performance might result from differences in amount and type of low-molecular weight carbohydrates and residual starch. Scanning electron microscopy (SEM) demonstrated that hydrolysis temperature changed substantially the structural appearance of flour particles. HPAF and CRF might find applications as dry milk extender and sweetener, respectively. (orig.).
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Directory of Open Access Journals (Sweden)
Paula Florence Sampaio
2014-08-01
Full Text Available O processo de educação de crianças e adolescentes por seus pais tem sido pouco valorizado em pesquisas que embasam ações de promoção de saúde e bem-estar infantil. Esta nota apresenta a primeira fase do processo de adaptação transcultural da versão brasileira para adolescentes do instrumento s-EMBU, que pretende aferir as práticas educativas parentais. Baseado no modelo universalista, este estudo focaliza as quatro primeiras etapas desse processo: avaliação das equivalências conceitual, de itens, semântica e operacional. Para tal, foram feitas revisão da literatura, discussão com especialistas, tradução e retrotradução dos itens. Entretanto, pré-teste realizado com dez adolescentes revelou que alguns itens ainda não captavam os construtos subjacentes pretendidos. Após mudanças em sua redação, esses foram compreendidos corretamente, conforme proposto pelo instrumento original. Os achados apresentados indicam que essa versão brasileira do s-EMBU para adolescentes parece promissora, devendo ser realizados estudos psicométricos futuros a fim de complementar seu processo de adaptação transcultural.
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Directory of Open Access Journals (Sweden)
RENATO REZENDE YOUNG BLOOD
2015-06-01
Full Text Available O objetivo deste trabalho foi avaliar a incidência em várias partes da planta e o desenvolvimento da antracnose do caquizeiro causada por Colletotrichum horiinas cultivares Fuyu e Kakimel produzidas sob os sistemas orgânico e convencional, respectivamente, nas safras de 2010/2011 e 2011/2012, em Campina Grande do Sul, Paraná, Brasil. Em cada pomar, 10 plantas foram selecionadas aleatoriamente, e 10 ramos do ano por planta, distribuídos ao redor dacopa, foram marcados para as avaliações de incidência de antracnose em ramos e folhas, a cada 15 dias. A quantificação de frutos caídos com ou sem sintomas da doença foi a cada 15 dias, durante o período de crescimento de frutos até a colheita, relacionada com a produção total. C. horii em flores foi avaliada em campo e também após incubação no laboratório. Infecção latente foi observada em frutos verdes coletados aos 90; 120 e 150 dias após a floração. Em ambas as safras, observou-se a queda de frutos com sintomas de antracnose entre os meses de janeiro e abril. C. horii é capaz de infectar flores, permanecer latente e provocar sintomas de antracnose em frutos imaturos. Frutos colhidos sadios apresentaram sintomas em pós-colheita após a incubação.
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Relação entre Fibrose e Arritmias Ventriculares na Cardiopatia Chagásica sem Disfunção Ventricular
Directory of Open Access Journals (Sweden)
Eduardo Marinho Tassi
2014-06-01
Full Text Available Fundamento: Pacientes com doença de Chagas com alteração segmentar apresentam pior prognóstico independentemente da fração de ejeção ventricular esquerda. A ressonância magnética cardíaca é atualmente o melhor método para detecção de alteração segmentar e para avaliação de fibrose miocárdica. Objetivo: Quantificar a fibrose, por meio do realce tardio, pela ressonância magnética cardíaca, em pacientes com doença de Chagas com fração de ejeção ventricular esquerda preservada ou minimamente comprometida (> 45% e detectar padrões de dependência entre fibrose, alteração segmentar e fração de ejeção ventricular esquerda na presença de arritmia ventricular. Métodos: Foram realizados eletrocardiograma, teste ergométrico, Holter e ressonância magnética cardíaca em 61 pacientes, separados em três grupos: (1 eletrocardiograma normal e ressonância magnética cardíaca sem alteração segmentar; (2 eletrocardiograma alterado e ressonância magnética cardíaca sem alteração segmentar; e (3 ressonância magnética cardíaca com alteração segmentar independentemente de alteração no eletrocardiograma. Resultados: O número de pacientes com arritmia ventricular em relação ao número total de pacientes em cada grupo, a porcentagem de fibrose e a fração de ejeção ventricular esquerda foram, respectivamente: no primeiro grupo, 4/26, 0,74% e 74,34%; no segundo grupo, 4/16, 3,96% e 68,5%; e no terceiro grupo, 11/19, 14,07% e 55,59%. Arritmia ventricular foi encontrada em 31,1% dos pacientes. Aqueles com e sem arritmia ventricular apresentaram fração de ejeção ventricular esquerda média de 59,87% e 70,18%, respectivamente, e fibrose de 11,03% e 3,01%, respectivamente. Das variáveis alteração segmentar, grupos, idade, fração de ejeção ventricular esquerda e fibrose, a última foi a única significativa para a presença de arritmia ventricular, com ponto de corte de 11,78% para massa fibrosada (p < 0
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Assessment of root surfaces of apicected teeth: A scanning electron ...
African Journals Online (AJOL)
Objectives: The aim of this study was to determine the apical surface characteristics and presence of dental cracks in single‑rooted premolars, resected 3.0 mm from the root apex, using the Er: YAG laser, tungsten carbide bur, and diamond‑coated tip, by scanning electron microscopy (SEM). Experimental design: Thirty ...
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Calibration-free quantitative surface topography reconstruction in scanning electron microscopy
Faber, E.T.; Martinez-Martinez, D.; Mansilla, C.; Ocelik, V.; De Hosson, J. Th. M.
This work presents a new approach to obtain reliable surface topography reconstructions from 2D Scanning Electron Microscopy (SEM) images. In this method a set of images taken at different tilt angles are compared by means of digital image correlation (DlC). It is argued that the strength of the
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Application of SEM/EDS to environmental geochemistry of heavy metals
Directory of Open Access Journals (Sweden)
Mateja Gosar
2009-06-01
Full Text Available Heavy metals represent a ubiquitous constituent of the near-surface environment, present in widely varyingconcentrations that typically have little impact on human behaviour and health. However, the mining of metals anduse of these metals in industrial processes has produced significant anthropogenic inputs of metals to both localand global environments. As such, a rigorous overview of the current accumulation of heavy metals and knowledgeof mineralogy of heavy metal-bearing phases is important for understanding their stability, solubility, mobility,bioavailability and toxicity. These data are of fundamental importance for environmental risk assessment and evaluationof future scenarios. Since conventional geochemical analyses provide limited information, other analyticalmethods have to be utilized for the characterisation of heavy metal-bearing phases. Significant analytical methodfor identification and characterisation of heavy metals in environmental media is a scanning electron microscopecoupled with energy dispersive X-ray spectrometer (SEM/EDS, an apparatus for qualitative and semi-quantitative chemical analysis at microne level, newly introduced to Geological Survey of Slovenia. Use of SEM/EDS was already introduced to environmental studies world-wide. In Slovenia, SEM/EDS analyses of environmental media werefirstly carried out on the Meža River stream sediments and snow deposits from Ljubljana urban area.Heavy metal-bearing phases in the Meža River stream sediments were apportioned to three source areas: Mežica mining/smelting area (geogenic-technogenic origin, Ravne ironworks area (technogenic origin and the Meža River catchment area (geogenic origin, which corresponds to data obtained by conventional geochemical and multivariate statistical methods. Airborne particles, identified in urban snow deposits, were interpreted as geogenic particles, represented by fragments of heavy metal-bearing minerals, and technogenic particles that
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NATURE AND LAW IN THE <em>INSTITUTAS> OF GAIO NATUREZA E DIREITO NAS <em>INSTITUTAS> DE GAIO
Directory of Open Access Journals (Sweden)
Alfredo Carlos Storck
2011-09-01
Full Text Available
In a very famous passage of his <em>Institutes>, the ancient jurist Gaius had divided the Roman Private Law in two parts: the Civil Law and the Law of People. The former is the Law created by the Roman people, whereas the latter is the Law followed by every nation.
Despite its classical origin, there is some disagreement among specialists about the right way to interpret this distinction. By the beginning of the 20th century, historians like Michel Villey had seen in this distinction the influence of Greek philosophy (Stoic but even Aristotelian among the Roman jurists. But Levy and more recently Kelly have challenged this view and proposed that, in the roman period, philosophers and jurists had completely distinct notions of nature and natural law. The aim of this paper is not to prove the exact influence of Greek philosophy among jurists, but only to suggest that it is not possible to give an interpretation of the classical texts without ascribing to them a theoretical notion of the natural law.Em uma famosa passagem de suas <em>Institutas>, o jurista romano Gaio dividiu o direito privado em duas partes: o direito civil e o direito dos povos. O primeiro é o direito criado pelo povo romano enquanto o segundo é o direito seguido por todas as nações. A despeito de sua origem clássica, os especialistas discordam acerca do modo de interpretar essa tese. No início do século XX, historiadores como Michel Villey viram na distinção sinais da influência da filosofia grega (estóica e mesmo aristotélica entre os juristas romanos. Posteriormente Levy e mais recentemente Kelly contestaram essa afirmação e defenderam que filósofos e juristas possuíam, no período clássico, noções de natureza e direito natural completamente distintas. O objetivo desse artigo não está em provar a exata influência da filosofia grega entre os juristas, mas apenas em sugerir que não é possível fornecer uma interpretação dos
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Automatic Registration of Scanned Satellite Imagery with a Digital Map Data Base.
1980-11-01
des images. ZUSAMMENFASSONG Die Auswertung digitaler Fernerkundungsbilder soll auf der gesamten Information beruhen, welche Uber das Interessensge...an . s . .caematei ......it .i.i~m I,. a~ecm istcc~aa ~.5n aa~n.m )eeIs* 6?In"IGmas &me$n e amc see.. mman a anmm. mm..em..a n a atee. eate sem ame
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Efeito da protease sobre o coeficiente de metabolizabilidade dos nutrientes em frangos de corte
Directory of Open Access Journals (Sweden)
C.F.Q. Matias
2015-04-01
Full Text Available Avaliaram-se os efeitos da protease sobre o coeficiente de metabolizabilidade dos nutrientes em dietas contendo farinha de penas (2,0% na fase inicial e 3,0% na fase de crescimento para frangos de corte machos, Cobb(r, de um a 32 dias de idade. Foram alojadas 336 aves em gaiolas metálicas equipadas com bandeja para coleta total de excretas. Foi utilizado delineamento inteiramente ao acaso, em arranjo fatorial 2x2 (com e sem adição da enzima protease 0,05% e duas valorizações da matriz nutricional da enzima, sendo sete repetições por tratamento, de 12 aves cada. Observou-se, na fase inicial, maior CMPB (P≤0,05 para as aves que, independentemente da adição de protease, consumiram ração com valorização da matriz nutricional da enzima. Não houve efeito dos tratamentos sobre o CMMS e o CMEE (P>0,05. Na fase de crescimento, houve interação entre os tratamentos para as variáveis CMPB e CMEE. Os frangos alimentados com dieta valorizada sem adição de enzima (controle negativo apresentaram melhores resultados (P≤0,05 para CMPB e CMEE. Nos tratamentos com enzima, o melhor CMEE (P≤0,05 foi obtido com o tratamento sem valorização da matriz nutricional (over the top. Conclui-se que níveis reduzidos e enzima sem valorização melhoram os coeficientes de metabolizabilidade dos nutrientes na fase adulta de frangos de corte.
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Studying antimicrobial-induced morphostructural damage of bacteria by Scanning Electron Microscope
Directory of Open Access Journals (Sweden)
Shruti Shukla
2015-12-01
Full Text Available In this investigation, a scanning electron microscopy (SEM method was used to examine the morphostructural changes in bacterial cells induced by antimicrobial agents. SEM-based visual approach is referred the study of bacterial cells and their physiological consequences when affected by antibiotics or antibacterial agents permitting the observation of characteristic morphological defects of cell wall, and provides valuable insights into processes involved in bacterial cell death. This experiment visualized various step-by-step techniques used in the slide preparation of bacterial cells treated with specific antimicrobial agent for analyzing the morphological alterations such as increase of cell wall roughness, cell disruption, cell swelling and lysed cell formation due to loss of intracellular material using SEM analysis when compared with untreated normal cells as a control. The SEM approach used in this visual experiment may analyze the antimicrobial effect of any commercially known or new compounds in a very conducive manner.
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Luis Antonio de Filippi Chaim
1992-01-01
Resumo: A eficácia de colutórios antiplaca, çem como de seus princípios ativos, foi determinada utilizando-se a inibição do metabolismo da placa dentária IN VITRO, como parâmetrode avaliaçãoo. A fermentação foi realizada incubando-se a suspensão de placa recente (lOmg/ml de tampão fosfato pH 6,8) em meio contendo glicose, com ou sem a adição de colutório, durante 2 horas, à 372C, com e sem a adição de Cloreto de Zinco o Os ácidos de fermentação foram tituladoscom NaOH O,OlNo A síntese de poli...
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A carga glicémica e as dietas hiperproteicas em cardiologia.
Santos, Alejandro
2008-01-01
São muitos os trabalhos que indicam que uma glicemia pós-prandial exagerada coloca indivíduos sem diabetes em maior risco de desenvolver doença cardiovascular. A maior elevação da glicemia (nos 120 minutos pós-refeição) e da hemoglobina glicada (HbA1c) estão associadas de forma independente à morbilidade e mortalidade cardiovascular em indivíduos não diabéticos. (...)
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Scanning tunneling microscopy and spectroscopy on GaN and InGaN surfaces
International Nuclear Information System (INIS)
Krueger, David
2009-01-01
Optelectronic devices based on gallium nitride (GaN) and indium gallium nitride (InGaN) are in the focus of research since more than 20 years and still have great potential for optical applications. In the first part of this work non-polar surfaces of GaN are investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM) and scanning tunneling microscopy (STM). In SEM and AFM, the (1 anti 100)- and especially the (anti 2110)-plane are quite corrugated. For the first time, the (anti 2110)-plane of GaN is atomically resolved in STM. In the second part InGaN quantum dot layers are investigated by X-ray photoelectron spectroscopy (XPS), scanning tunneling spectroscopy (STS) and STM. The STMmeasurements show the dependency of surface morphology on growth conditions in the metalorganic vapour phase epitaxy (MOVPE). Nucleation, a new MOVPE-strategy, is based on phase separations on surfaces. It is shown that locally varying density of states and bandgaps can be detected by STS, that means bandgap histograms and 2D-bandgap-mapping. (orig.)
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An evaluation testing technique of single event effect using Beam Blanking SEM
Energy Technology Data Exchange (ETDEWEB)
Aoki, J; Hada, T; Pesce, A; Akutsu, T; Matsuda, S [National Space Development Agency of Japan, Tsukuba, Ibaraki (Japan). Tsukuba Space Center; Igarashi, T; Baba, S
1997-03-01
Beam Blanking SEM (Scanning Electron Microscope) testing technique has been applied to CMOS SRAM devices to evaluate the occurence of soft errors on memory cells. Cross-section versus beam current and LET curves derived from BBSEM and heavy ion testing technique, respectively, have been compared. A linear relation between BBSEM current and heavy ion LET has been found. The purpose of this study was to demonstrate that the application of focused pulsed electron beam could be a reliable, convenient and inexpensive tool to investigate the effects of heavy ions and high energy particles on memory devices for space application. (author)
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Contact detection for nanomanipulation in a scanning electron microscope
Energy Technology Data Exchange (ETDEWEB)
Ru, Changhai, E-mail: rchhai@gmail.com [Automation College, Harbin Engineering University, Harbin 150001 (China); Robotics and Microsystems Center, Soochow University, Jiangsu 215021 (China); To, Steve, E-mail: Steve.to@utoronto.ca [Department of Mechanical and Industry Engineering, University of Toronto, Ontario, Canada M5S3G8 (Canada)
2012-07-15
Nanomanipulation systems require accurate knowledge of the end-effector position in all three spatial coordinates, XYZ, for reliable manipulation of nanostructures. Although the images acquired by a scanning electron microscope (SEM) provide high resolution XY information, the lack of depth information in the Z-direction makes 3D nanomanipulation time-consuming. Existing approaches for contact detection of end-effectors inside SEM typically utilize fragile touch sensors that are difficult to integrate into a nanomanipulation system. This paper presents a method for determining the contact between an end-effector and a target surface during nanomanipulation inside SEM, purely based on the processing of SEM images. A depth-from-focus method is used in the fast approach of the end-effector to the substrate, followed by fine contact detection. Experimental results demonstrate that the contact detection approach is capable of achieving an accuracy of 21.5 nm at 50,000 Multiplication-Sign magnification while inducing little end-effector damage. -- Highlights: Black-Right-Pointing-Pointer We presents a simple method for obtaining the depth information in SEM-based nanomanipulation. Black-Right-Pointing-Pointer Detecting contact between an end-effector and a target surface using SEM as a vision sensor. Black-Right-Pointing-Pointer Additional touch/force sensors or specialized hardware need not be added. Black-Right-Pointing-Pointer Achieved high repeatability and accuracy. Black-Right-Pointing-Pointer Complete automatic contact detection within typically 60 s.
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Avaliação ecocardiográfica em obesos graves assintomáticos
Rocha,Isaura Elaine Gonçalves Moreira; Victor,Edgar Guimarães; Braga,Maria Cynthia; Silva,Odwaldo Barbosa e; Becker,Mônica de Moraes Chaves
2007-01-01
OBJETIVO: Estudar a função sistólica e diastólica por meio da ecocardiografia Doppler em pacientes assintomáticos com obesidade grave. MÉTODOS: Foram avaliados, por meio de ecocardiograma transtorácico, 30 pacientes candidatos a cirurgia bariátrica, com IMC médio de 49,2±8,8 kg/m², sem história de cardiopatia prévia. RESULTADOS: Observou-se aumento de câmaras esquerdas em 42,9% da amostra, disfunção diastólica em 54,6%, hipertrofia ventricular esquerda em 82,1%, com padrão geométrico do tipo ...
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Directory of Open Access Journals (Sweden)
Miguel Fernandes Felippe
2014-09-01
Full Text Available As nascentes de cursos d’água são sistemas hidrogeomorfológicos complexos, caracterizados por uma grande variabilidade de seus elementos estruturantes. Esta heterogeneidade ainda pouco conhecida cria dificuldades para os processos de gestão ambiental, pois, em teoria, cada nascente responde a perturbações de maneira diferente. Nesse sentido, este trabalho tem como objetivo desenvolver uma tipologia de nascentes com base em suas características hidrogeomorfológicas que sistematize sua heterogeneidade, sem perder seus aspectos individuais. Para atingir esta meta um método de máxima verossimilhança baseado na teoria dos conjuntos nebulosos foi usado para criar perfis multivariados para 79 nascentes catalogadas em três parques urbanos de Belo Horizonte - MG. Após uma série de testes estatísticos, propuseram-se seis tipos básicos no qual as nascentes podem ser enquadradas. No entanto, o principal avanço desta técnica é permitir a comparação entre os diferentes graus de pertencimento de cada nascente em cada tipo criado, auxiliando na compreensão da sua diversidade, sem esconder a sua heterogeneidade.
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O sistema "UFSC sem papel” sob a perspectiva da inovação
Directory of Open Access Journals (Sweden)
Naira Silva
2013-04-01
Full Text Available DOI: http://dx.doi.org/10.5007/2175-8077.2013v15n35p11 O presente artigo tem como objetivo analisar o sistema de informação “UFSC sem papel” sob a ótica da inovação. Para tanto, fez-se uso da pesquisa descritiva e do estudo de caso, com abordagem qualitativa. Apresenta uma perspectiva de estudo transversal, considerando-se o período compreendido entre outubro de 2011 a novembro de 2011. Trata-se, ainda, de uma pesquisa de campo, bibliográfica. O sujeito da pesquisa, escolhido por tipicidade, foi o superintendente da Superintendência de Governança Eletrônica e Tecnologia da Informação e Comunicação (SeTIC, da Universidade Federal de Santa Catarina. Para a coleta de dados, foi utilizada a entrevista semi-estruturada, a partir de um roteiro, sendo os dados analisados por meio da técnica pattern-matching. O sistema analisado é uma inovação técnica e radical, com efeitos sobre o âmbito administrativo, sendo dividido em módulos para a gestão dos processos administrativos (protocolo, de compras e licitações, de patrimônio e de materiais e almoxarifado. A sua finalidade é modernizar as atividades administrativas, reduzindo o uso de papel e gerando maior rapidez na tramitação dos documentos, mais transparência e maior eficiência na execução dos processos da organização. Em termos de desenvolvimento e aquisição da citada inovação, a UFSC fez opção pela compra de um pacote pronto, mas a implantação foi acompanhada pela equipe da SeTIC. Há certa preocupação com relação à falta de habilidade das pessoas em utilizá-lo. Conclui-se sobre a necessidade de conduzir uma apurada análise do sistema “UFSC sem Papel”, para que tal inovação possa ser bem sucedida.
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Moore, Jayma A; Payne, Scott A
2012-01-01
Fungi often are found within plant tissues where they cannot be visualized with the scanning electron microscope (SEM). We present a simple way to reveal cell interiors while avoiding many common causes of artifact. Freeze-fracture of leaf tissue using liquid nitrogen during the 100% ethanol step of the dehydration process just before critical point drying is useful in exposing intracellular fungi to the SEM.
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Prombonas, Anthony; Yannikakis, Stavros; Karampotsos, Thanasis; Katsarou, Martha-Spyridoula; Drakoulis, Nikolaos
2016-01-01
Introduction Surface integrity of dental elastomeric impression materials that are subjected to disinfection is of major importance for the quality of the final prosthetic restorations. Aim The aim of this qualitative Scanning Electronic Microscopy (SEM) study was to reveal the effects of immersion or ozone disinfection on the surface of four dental elastomeric impression materials. Materials and Methods Four dental elastomeric impression material brands were used (two vinyl polysiloxane silicones, one polyether, and one vinyl polyether silicone). Total of 32 specimens were fabricated, eight from each impression material. Specimens were immersion (0.525% sodium hypochlorite solution or 0.3% benzalkonium chloride solution) or ozone disinfected or served as controls and examined with SEM. Results Surface degradation was observed on several speci-mens disinfected with 0.525% sodium hypochlorite solution. Similar wavy-wrinkling surface structures were observed in almost all specimens, when treated either with 0.3% benzalkonium chloride solution or ozone. Conclusion The SEM images obtained from this study revealed that both immersion disinfectants and ozone show similar impression material surface alterations. Ozone seems to be non-inferior as compared to immersion disinfectants, but superior as to environmental protection. PMID:28208993
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Directory of Open Access Journals (Sweden)
Vladimir José Ferrari
2002-04-01
Full Text Available O desprendimento dos laminados de plásticos reforçados com fibras da face inferior tracionada das vigas reforçadas à flexão é um problema complexo e indesejável, pois ocorre sem aviso, antecipando a ruína da viga reforçada e impossibilitando o total aproveitamento das propriedades resistentes à tração do reforço. Neste trabalho estudou-se o comportamento de vigas de concreto armado, reforçadas à flexão com manta de fibra de carbono, e avaliou-se a incorporação de mecanismos de incremento de ancoragem para evitar o desprendimento prematuro da manta com conseqüente aumento da capacidade resistente à flexão da viga. Nove vigas foram divididas em cinco grupos em conformidade com mecanismo de incremento de ancoragem adotado. Um dos mecanismos, além de evitar o desprendimento prematuro do reforço, também proporcionou incremento na resistência à flexão mais de 95%, em relação à viga sem reforço, e incrementos em torno de 20%, em relação às vigas sem incremento de ancoragem.
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International Nuclear Information System (INIS)
Fuente, D. de la; Alcántara, J.; Chico, B.; Díaz, I.; Jiménez, J.A.; Morcillo, M.
2016-01-01
Highlights: • SEM/Micro-Raman is very useful for characterizing rust phases morphologies. • SEM/Micro-Raman enables unequivocal rust phases identification. • γ-FeOOH basically presents two types of morphologies: globular and laminar. • Fe 3 O 4 presents two morphologies: flat patches and black doughnut-type formations. • β-FeOOH presents highly porous morphologies comprised by fine prismatic crystals. - Abstract: The exposure of mild steel to marine atmospheres gives rise to the formation of various corrosion products, mainly lepidocrocite, goethite, magnetite and akaganeite. In this study, Grazing Incidence X-Ray Diffraction, Micro-X-Ray Diffraction and Scanning Electron Microscopy/Micro-Raman are used to characterise rust layer surfaces and to identify the principal component rust phases and their morphology. The main conclusion reached is that lepidocrocite is preferentially located on the outermost surface while magnetite and akaganeite form mostly close to base steel. The Scanning Electron Microscopy/Micro-Raman technique has been very useful for characterising (identifying) the wide variety of morphologies presented by the rust phases.
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Directory of Open Access Journals (Sweden)
Rudimar Mafacioli
2011-03-01
Full Text Available
A antracnose, causada pelo fungo <em>Colletotrichum loeosporioides>, é a principal doença da parte aérea da pupunheira (<em>Bactris gasipaes em>var gasipaes em viveiros de mudas no Centro-Sul do Brasil. O objetivo do trabalho foi avaliar a eficiência de novas formulações de fungicidas no controle de antracnose em mudas de pupunheira, na fase de viveiro. O ensaio foi conduzido no período de abril a agosto de 2006, com o delineamento experimental em blocos ao acaso, com cinco tratamentos com fungicidas e uma testemunha sem fungicida, com quatro repetições. As parcelas foram constituídas por dez mudas. Foram avaliados os seguintes fungicidas através de pulverização da parte aérea: piraclostrobina+epoxiconazole (0,13 + 0,05 g.L-1, tetraconazole (0,1 g.L-1, tebuconazole (0,2 g.L-1, chlorotalonil (2 g.L-1 e chlorotalonil+tiofanato metílico(1 + 0,4 g.L-1. A severidade (percentagem da área foliar doente a doença foi avaliada quinze dias após a sétima aplicação (última. Verificou-se que todos os tratamentos com fungicidas proporcionaram redução estatisticamente significativa na intensidade da doença em relação à testemunha sem fungicida (P £ 0,05. Os tratamentos com os diferentes fungicidas não diferiram significativamente entre si. Os fungicidas avaliados proporcionaram índice de controle da doença de 68 % a 78 %.Leaf anthracnose, caused by <em>Colletotrichum loeosporioides>, is the most important disease of peach palm plants (<em>Bactris gasipaes em>var. gasipaes in nurseries in the Central and Southern Brazil. The objective of this study was to evaluate efficacy of some new formulations of fungicides for controlling anthracnose transplants in orchards. An assay with randomized block design was carried out, with five different fungicides and a control, with four replicates. Each replicated had 10 plants. The fungicides evaluated were: piraclostrobin + epoxiconazoleSpecimen's plane misaligned installation solution based on charge fluctuation inside SEM
Lu, Haojian; Liu, Yanting; Yang, Yuanyuan; Wang, Panbing; Shen, Yajing
2018-04-01
Precise specimen's installation is a sticking point to ensure the characterization accuracy of the in-situ material property test. Although it is common knowledge that specimen's plane misaligned installation (PMI) would cause extra force loading during mechanical testing, there are few effective solutions available to deal with it at the current stage, especially during the in-situ scanning electron microscopy (SEM) test. Taking into consideration the charge fluctuation phenomenon under SEM, this paper proposes a highlight area variation (HAV) method for specimen deformation judgment, i.e., the specimen deformation is defined when the highlight area changes greater than 20% of the initial value of the specimen surface. Three types of specimens with different resistivities, i.e., human hair (electrical resistivity ˜3 × 1012 Ω cm), optical fiber (electrical resistivity ˜1017 Ω cm), and magnetic wire (electrical resistivity ˜2 × 10-5 Ω cm), are chosen to verify the effectiveness of the HAV method. Furthermore, combined with the developed robot-aided alignment system, the specimen's PMI problem can also be solved. In the demonstration, the human hair specimen is installed across two specimen stages and its in-situ twisting (in 360°) test is implemented. The results clearly indicate that the HAV method and the robot-aided alignment system are practical and reliable, and the specimen can be aligned on the same plane and installed precisely with accuracy up to 3 μm. This method will benefit the in-situ SEM material mechanical property test and has a significant impact in fundamental material research.
Directory of Open Access Journals (Sweden)
Rodrigo Milani
2005-01-01
Full Text Available OBJETIVO: Analisar os resultados imediatos da operação para revascularização do miocárdio sem circulação extracorpórea em pacientes acima de 75 anos. MÉTODOS: De janeiro 2001 a dezembro 2003, 193 pacientes com idade variando de 75 a 94 anos, correspondendo a 100% das operações coronarianas realizadas em pacientes acima de 75 anos, sendo 121 homens e 72 mulheres, foram submetidos a operação para revascularização do miocárdio sem circulação extracorpórea e analisados, retrospectivamente, os dados de internação dos pacientes. RESULTADOS: A hipertensão arterial esteve presente em 174 (90%, seguida de dislipidemia em 115 (59%, tabagismo em 89 (46% e diabetes em 57 (29%, e 96 (49,7% com antecedente de infarto do miocárdio. Destes, 53 (27,4% tinham apresentado evento isquêmico agudo em um período OBJECTIVE: To assess the immediate results of myocardial revascularization surgery without extracorporeal circulation in a group of patients over 75 years of age. METHODS: From January 2001 to December 2003, 193 (121 men and 72 women patients with ages ranging from 75 to 94 years, corresponding to 100% of the coronary surgeries performed in patients over the age of 75 years, underwent myocardial revascularization without extracorporeal circulation. Their hospitalization data were retrospectively analyzed. RESULTS: Arterial hypertension was present in 174 (90%, dyslipidemia in 115 (59%, smoking in 89 (46%, and diabetes in 57 (29%. Ninety-six (49.7% patients had had a previous myocardial infarction, 53 of whom (27.4% had experienced an acute ischemic event in a period < 30 days after surgery. Critical obstructive lesions in 3 or more coronary vessels were present in 156 (80.95% patients, while 30 (15% patients had an important obstruction of the left main coronary artery, and 30 (15% patients had an ejection fraction < 30%. The score obtained according to the EUROSCORE ranged from 3 to 18, with an expected mortality rate for the group of
Freitas,Karine C.; Motta,Maria Eugênia F. A.; Amâncio,Olga M. S.; Fagundes Neto,Ulysses; Morais,Mauro B.
2004-01-01
OBJETIVO: Comparar, em ratos, o efeito do polissacarídeo de soja em relação a celulose e fórmula de soja sem fibra alimentar sobre o peso e a umidade fecal. MÉTODOS: Foram utilizados 12 ratos Wistar machos, com 21 dias de vida, distribuídos em três grupos, que receberam ração AIN-93G variando-se a fonte de fibra alimentar: grupo polissacarídeo, com 5% de fibra na forma de polissacarídeo de soja; grupo fórmula de soja, com 5% de fórmula de soja sem fibra; e grupo celulose, com 5% de fibra na f...
Sem sol nem tempestade: caracteres de Iaiá Garcia em ruína
Directory of Open Access Journals (Sweden)
Cilaine Alves Cunha
Full Text Available O artigo discute o desvio, realizado por Machado de Assis em Iaiá Garcia, das expectativas da narrativa sentimental e a comparação estabelecida entre os dois triângulos amorosos: Jorge, Estela e Luís Garcia, de um lado, e Estela, Jorge e Iaiá Garcia, de outro. Considerando a ação das paixões e do sistema escravocrata na conduta das personagens, aborda o confronto entre a convenção do amor paixão e a instituição do casamento como instrumento de ascensão social.
Imunolocalização da podoplanina em tumores odontogênicos benignos
Adriana dos Santos Caetano
2011-01-01
A podoplanina humana é uma glicoproteína que se expressa em várias células e tecidos normais e neoplásicos, inclusive aqueles de origem odontogênica. O objetivo deste estudo foi identificar a imunolocalização da podoplanina em tumores odontogênicos epiteliais com e sem ectomesênquima incluindo oito ameloblastomas, nove tumores odontogênicos adenomatóides, vinte tumores odontogênicos queratocísticos, cinco cistos odontogênicos ortoqueratinizados, um tumor odontogênico epitelial calcificante,...