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排序方式: 共有540条查询结果,搜索用时 31 毫秒
1.
Ricardo Cambraia Parreira Diana Paola Gmez‐Mendoza Itamar Couto Guedes de Jesus Rafael Pereira Lemos Anderson Kennedy Santos Cristiana Perdigo Rezende Henrique Csar Pereira Figueiredo Mauro Cunha Xavier Pinto Frank Kjeldsen Silvia Guatimosim Rodrigo Ribeiro Resende Thiago Verano‐Braga 《Proteomics. Clinical applications》2020,14(4)
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Imaging of the optic disc and retinal nerve fiber layer: the effects of age, optic disc area, refractive error, and gender. 总被引:3,自引:0,他引:3
Christopher Bowd Linda M Zangwill Eytan Z Blumenthal Cristiana Vasile Andreas G Boehm Parag A Gokhale Kourosh Mohammadi Payam Amini Timothy M Sankary Robert N Weinreb 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(1):197-207
We cross-sectionally examined the relationship between age, optic disc area, refraction, and gender and optic disc topography and retinal nerve fiber layer (RNFL) measurements, using optical imaging techniques. One eye from each of 155 Caucasian subjects (age range 23.0-80.8 y) without ocular pathology was included. Measurements were obtained by using the Heidelberg Retina Tomography (HRT), the GDx Nerve Fiber Analyzer, and the Optical Coherence Tomograph (OCT). The effects of age were small (R2 < 17%) and were limited to specific HRT, GDx, and OCT parameters. Disc area was significantly associated with most HRT parameters and isolated GDx and OCT parameters. Refraction and gender were not significantly associated with any optic disc or RNFL parameters. Although effects of age on the optic disc and RNFL are small, they should be considered in monitoring ocular disease. Optic disc area should be considered when cross-sectionally evaluating disc topography and, to a lesser extent, RNFL thickness. 相似文献
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Renato Maia Renato Cerqueira Clarisse Sieckenius de Souza Tomás Guisasola-Gorham 《Empirical Software Engineering》2012,17(3):166-199
Today middleware is much more powerful, more reliable and faster than it used to be. Nevertheless, for the application developer,
the complexity of using middleware platforms has increased accordingly. The volume and variety of application contexts that
current middleware technologies have to support require that developers be able to anticipate the widest possible range of
execution environments, desired and undesired effects of different programming strategies, handling procedures for runtime
errors, and so on. This paper shows how a generic framework designed to evaluate the usability of notations (the Cognitive Dimensions of Notations Framework, or CDN) has been instantiated and used to analyze the cognitive
challenges involved in adapting middleware platforms. This human-centric perspective allowed us to achieve novel results compared
to existing middleware evaluation research, typically centered around system performance metrics. The focus of our study is
on the process of adapting middleware implementations, rather than in the end product of this activity. Our main contributions
are twofold. First, we describe a qualitative CDN-based method to analyze the cognitive effort made by programmers while adapting
middleware implementations. And second, we show how two platforms designed for flexibility have been compared, suggesting
that certain programming language design features might be particularly helpful for developers. 相似文献
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Luccas M. Barata Eloísa H. Andrade Alessandra R. Ramos Oriel F. de Lemos William N. Setzer Kendall G. Byler Jos Guilherme S. Maia Joyce Kelly R. da Silva 《International journal of molecular sciences》2021,22(2)
This study evaluated the chemical compositions of the leaves and fruits of eight black pepper cultivars cultivated in Pará State (Amazon, Brazil). Hydrodistillation and gas chromatography–mass spectrometry were employed to extract and analyze the volatile compounds, respectively. Sesquiterpene hydrocarbons were predominant (58.5–90.9%) in the cultivars “Cingapura”, “Equador”, “Guajarina”, “Iaçará”, and “Kottanadan”, and “Bragantina”, “Clonada”, and “Uthirankota” displayed oxygenated sesquiterpenoids (50.6–75.0%). The multivariate statistical analysis applied using volatile composition grouped the samples into four groups: γ-Elemene, curzerene, and δ-elemene (“Equador”/“Guajarina”, I); δ-elemene (“Iaçará”/“Kottanadan”/“Cingapura”, II); elemol (“Clonada”/“Uthirankota”, III) and α-muurolol, bicyclogermacrene, and cubebol (“Bragantina”, IV). The major compounds in all fruit samples were monoterpene hydrocarbons such as α-pinene, β-pinene, and limonene. Among the cultivar leaves, phenolics content (44.75–140.53 mg GAE·g−1 FW), the enzymatic activity of phenylalanine-ammonia lyase (20.19–57.22 µU·mL−1), and carotenoids (0.21–2.31 µg·mL−1) displayed significant variations. Due to black pepper’s susceptibility to Fusarium infection, a molecular docking analysis was carried out on Fusarium protein targets using each cultivar’s volatile components. F. oxysporum endoglucanase was identified as the preferential protein target of the compounds. These results can be used to identify chemical markers related to the susceptibility degree of black pepper cultivars to plant diseases prevalent in Pará State. 相似文献
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V. Spitzer F. Marx J. G. Maia K. Pfeilsticker 《European Journal of Lipid Science and Technology》1991,93(5):169-174
Four acetylenic fatty acids [11-octadecen-9-ynoic acid (E) (ximenynic acid), 11-octadecen-9-ynoic acid (Z), 9,11-octadecadiynoic acid and 13-octadecen-9,11-diynoic acid (E) (exocarpic acid)] were found in the seed oil of Curupira tefeensis (Olacaceae) as minor compounds. The mass spectra of the methyl esters (EI and CI mode), picolinyl esters and 4,4-dimethyloxazoline derivatives of these acids are discussed in detail. Furthermore the NMR data of 9,11-octadecadiynoic acid and 13-octadecen-9,11-diynoic acid are presented. 相似文献
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V. Spitzer F. Marx K. Pfeilsticker J. G. S. Maia 《European Journal of Lipid Science and Technology》1994,96(10):395-396
The mass spectra of the picolinyl derivatives of two natural occurring cyclopropenoid fatty acids (malvalic and sterculic acid) showed, besides the typical peaks for picolinyl derivatives, a characteristic gap of 66 amu between the two allylic positions of the ring system. This phenomenon could be used for the determination of the ring position of this type of fatty acids. 相似文献
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In Part 1 of this work, the possibility of improving single-screw extruders (SSE) better dispersive mixer was explored by harnessing extensional flows provided by the hyperbolic contracting–diverging channels of extensional mixing elements (EME). Addition of the EME to the pin screw generated enhanced breakup for polymer blends and nanocomposite systems without significant penalty in flow rate. In Part 2, experiments are performed on immiscible polymer blends (low-viscosity ratio and high-viscosity ratio) and nanocomposites on both SSE and twin-screw extruder (TSE) with the same rotation speed and throughput. Morphological results show tremendous improvement in dispersive mixing capability of SSE when equipped with EME that are mainly comparable to conventional TSE that is, with kneading blocks as mixing sections, although not as good as TSEs equipped with EMEs. Mechanical results also show enhanced modulus when EME is used in SSE operations. 相似文献
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