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201.
Luís F. R. Lucas Nuno M. M. Rodrigues Carla L. Pagliari Eduardo A. B. da Silva Sérgio M. M. de Faria 《Multidimensional Systems and Signal Processing》2017,28(4):1393-1416
The Multidimensional Multiscale Parser (MMP) is a pattern-matching-based generic image encoding solution which has been investigated earlier for the compression of stereo images with successful results. While first MMP-based proposals for stereo image coding employed dictionary-based techniques for disparity compensation, posterior developments have demonstrated the advantage of using predictive methods. In this paper, we focus on recent investigations on the use of predictive methods in the MMP algorithm and propose a new prediction framework for efficient stereo image coding. This framework comprises an advanced intra directional prediction model and a new linear predictive scheme for efficient disparity compensation. The linear prediction model is the main novelty of this work, combining adaptive linear models estimated by least-squares algorithm with fixed linear models provided by the block-matching algorithm. The performance of the proposed intra prediction and disparity compensation methods when applied in an MMP encoder has been evaluated experimentally. Comparisons with the current stereo image coding standards showed that the proposed MMP algorithm significantly outperforms the Stereo High Profile of H.264/AVC standard. In addition, it presents a competitive performance relative to the MV-HEVC standard. These results also suggest that current stereo image coding standards may benefit from the proposed linear prediction scheme for disparity compensation, as an extension to the omnipresent block-matching solution. 相似文献
202.
203.
Morphology of laryngeal cartilage of the nine‐banded armadillo (Dasypus novemcinctus) Linnaeus, 1758
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Clarisse Maria Barbosa Fonseca Andrezza Braga Soares da Silva Maria Michele Araújo de Sousa Cavalcante Ingrid Macedo de Oliveira Selma Maria Santos Moura Bruno Melo Cunha Carla Maria de Carvalho Leite Maria Acelina Martins de Carvalho Waldilleny Ribeiro de Araújo Moura Márcia dos Santos Rizzo Airton Mendes Conde Júnior 《Microscopy research and technique》2017,80(10):1089-1095
Armadillos, Xenarthras representatives, known for adaptability to different ecosystems, own specific morphophysiological characteristics that are not known and deserve to be studied. The aim of this study was to describe the morphology of cartilage of the larynx of the nine‐banded armadillo (Dasypus novemcinctus). Five dead armadillos were donated by the Chico Mendes Institute of Biodiversity (ICMBio‐PI) to the Federal University of Piauí. The animals were fixed and dissected for removal of the larynx. The cartilages were identified and described, photodocumented, and schematized. Fragments with about 0.5 cm of each cartilage were collected and submitted to classical histology for Hematoxylin–Eosin coloring. The slides were assembled in enterlan and analyzed under a light microscope. The larynx of the armadillo (D. novemcinctus) is located in the mentonian region, ventral to the esophagus, and due to the total positioning of the tongue in the oral cavity, there is also a cranial cervical position in this species. The larynx has five cartilages, they are: a cricoid, a thyroid, an epiglottis, and two arytenoids. The corniculate process is present; however, the cuneiform process is absent. The epiglottis has a discrete bifurcation at its apex. In all cartilages epithelial variations are observed. The tissues are varied from squamoso stratified to cylindrical pseudostratified, with propria lamina rich in mucoserosas glands. With the exception of epiglottic cartilage, predominantly elastic, the rest are hyaline. The larynx of D. novemcinctus, although the same number of cartilages, differs morphologically and microscopically from the larynx of other species. 相似文献
204.
Suitable conditioning plant design is only one aspect of a wide problem that concerns thermo-physical building performance and then building envelope characteristics quality. This is really very important when a building is a museum and work of art at the same time, like the Hall of the Five Hundred that is the object of our study. Its need for conditioning is due to its prestige utilization for public meetings; but it must be seen as connected to different interventions for energy saving and rational energy use. Because of the architectural structure of the Hall and lack of space for plant allocation, the solution proposed in this paper is based on the minimum impact and reversibility concept. A movable platform on the existing floor that can hold all plants was proposed. This thin radiant panel solution was studied by a CFD simulation based on the finite volume method in transient conditions. In order to obtain reliable information concerning the fluid dynamic and thermal fields, the simulations were performed by using experimental data carried out by the Opificio delle Pietre Dure as comparison. 相似文献
205.
Photodegradation study of three dipyrone metabolites in various water systems: identification and toxicity of their photodegradation products 总被引:1,自引:0,他引:1
The photochemical behaviour of three relevant metabolites of the analgesic and antipyretic drug dipyrone, 4-methylaminoantipyrine (4-MAA), 4-formylaminoantipyrine (4-FAA) and 4-acetylaminoantipyrine (4-AAA), was evaluated under simulated solar irradiation (Suntest system). For 4-MAA, different aqueous solutions (synthetic seawater, freshwater and Milli-Q water) as well as different operational conditions were compared. According to the experimental results, 4-MAA resulted as being an easily degraded molecule by direct photolysis, with half-life times (t1/2) ranging from 0.12 to 0.58 h, depending on the irradiation conditions. Faster degradation was observed in synthetic waters, suggesting that the photolysis was influenced by the salt composition of the waters. However, no effect on the degradation rate was observed by the presence of natural photosensitizers (dissolved organic matter, nitrate ions). 4-FAA and 4-AAA showed slower photodegradation kinetics, with t1/2 of 24 and 28 h, respectively. A study of photoproduct identification was carried out by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-time-of-flight mass spectrometry (LC-TOF-MS) (ESI positive mode), which allowed us to propose a tentative photodegradation pathway for 4-MAA and the identification of persistent by-products in all the cases. Finally, the application of an acute toxicity test (Daphnia magna) showed an increase in toxicity during the photolytic process, a consequence of the formation of toxic photoproducts. 相似文献
206.
Viganò L Arillo A Buffagni A Camusso M Ciannarella R Crosa G Falugi C Galassi S Guzzella L Lopez A Mingazzini M Pagnotta R Patrolecco L Tartari G Valsecchi S 《Water research》2003,37(3):501-518
Comprehensive and contemporary evaluations of physical, chemical and toxicological endpoints have been performed on bed sediments of the Po River, the major Italian watercourse. Two extensive sampling campaigns were conducted in summer and winter low-flow conditions. Composite sediment samples were collected from ten reaches of the main river: the first was located in the upper region (ambient control), and the others downstream of the confluences of nine principal tributaries. The two sampling programs were paralleled by contemporary investigations on the macroinvertebrate community. The particle-size composition along the Po River showed a relatively uniform distribution of fine sand, a progressive downstream decrease of coarse sands and a corresponding increase of fine materials. The levels of polychlorinated biphenyls (PCB), polycyclic aromatic hydrocarbons (PAH), extractable organo halides (EOX), Cd, Cr, Cu, Hg, Ni, Pb and Zn were determined in sediment fine particles (< 63 microm), and showed marked changes across the ten river reaches. Their longitudinal trends, as those of organic carbon and total nitrogen, were very similar and largely independent of the survey season. Sediment quality benchmarks were used to evaluate sediment chemistry, and, although the overall level of contamination was from moderate to low, the reaches located downstream of the tributaries Dora Riparia, Dora Baltea, Lambro and Oglio were considered to be at risk. Sediments were tested for toxicity on Oncorhynchus mykiss, Ceriodaphnia dubia, Raphidocelis subcapitata and Vibrio fischeri. The toxicity tests were conducted both with sediment extracts and whole samples. Sediment extracts showed toxic potentials that were consistent with the spatial distribution of contaminants. Whole-sediment toxicity showed moderate/low effects which also included false positives and negatives. Alterations of the macroinvertebrate community were found for many kilometers downstream of Dora Riparia, and with a seasonal dependence, also in other reaches of the Italian river. Principal component analysis (PCA) was used to describe the longitudinal and temporal changes of the Po River, and allowed the selection of the most useful and discriminating indicators. 相似文献
207.
Coelho GL Dornelas CB Soares KC dos Santos EP Vergnanini AL dos Santos TC Rodrigues CR Castro HC Dias LR Cabral LM 《Drug development and industrial pharmacy》2008,34(5):536-546
Herein we describe inclusion complexes of commercial sunscreens in cyclodextrins and montmorillonites to generate new sunscreen derivatives with optimized functional properties such as water resistance and skin adherence. Four cyclodextrins (alpha-, beta-, and gamma-cyclodextrin, and beta-dimethyl cyclodextrin) and two montmorillonites (sodium and alkylammonium) were investigated for encapsulating some commercial sunscreens. Our results reveal a good yield and inclusion products with functional properties obtained by using kneading technique on Eusolex 2292 and Eusolex 6007 in beta-cyclodextrin and solubilization method on Eusolex 6007 and NeoHeliopan MA in montmorillonite. In addition, molecular modeling studies indicated flexibility as important for the intercalation of the host molecule. 相似文献
208.
Causin V Marega C Marigo A Ferraro G Ferrara A Selleri R 《Journal of nanoscience and nanotechnology》2008,8(4):1823-1834
Nanocomposites based on isotactic polypropylene/ethylene propylene rubber (iPP/EPR) were prepared adding different amounts of montmorillonite and maleated polypropylene. The structure and morphology of the samples were characterized by small angle X-ray scattering, wide angle X-ray diffraction, electronic and optical microscopy and differential scanning calorimetry, iPP showed a polymorphic behavior. Clay disrupted the ordered crystallization of iPP and had a key role in shaping the distribution of iPP and EPR phases: larger filler contents brought about smaller, less coalesced and more homogeneous rubber domains. Clay distributed itself only in the continuous phase and not in the rubber domains. Tactoids persisted on the surface of the sample, while delamination proceeded to a greater degree in the bulk of the materials. Melt flow rate, impact strength, flexural and tensile properties, were also measured and a structure-property correlation was sought. Clay produced its most significant effect on physical-mechanical properties by controlling the size of rubber domains in the heterophasic matrix. This allowed to obtain nanocomposites with increased stiffness and impact strength, a remarkable achievement for polymer layered-silica nanocomposites that usually suffer the drawback of being stiffer than the unfilled matrix, but at the same time with a lower resistance to impact. A beneficial effect of clay on thermal stability was also observed. 相似文献
209.
Lobel Marci; Cannella Dolores Lacey; Graham Jennifer E.; DeVincent Carla; Schneider Jayne; Meyer Bruce A. 《Canadian Metallurgical Quarterly》2008,27(5):604
Objective: Stress in pregnancy predicts earlier birth and lower birth weight. The authors investigated whether pregnancy-specific stress contributes uniquely to birth outcomes compared with general stress, and whether prenatal health behaviors explain this association. Design: Three structured prenatal interviews (N = 279) assessing state anxiety, perceived stress, life events, pregnancy-specific stress, and health behaviors. Main Outcome Measures: Gestational age at delivery, birth weight, preterm delivery ( 相似文献
210.
Cultural worldviews and perceived racial discrimination were examined among Americans (n = 106) and British Caribbean Americans (n = 95), both of African descent, who were recruited through university student organizations, community organizations, and snowball sampling. Consistent with public perceptions of differences in the experience of race among these 2 groups, multiple regression analyses revealed African Americans were more likely than British Caribbean Americans to perceive racial discrimination in the United States. In addition, a cultural worldview focus on individuality and equality (i.e., horizontal individualism) moderated the relationship between ethnic group and perceived racial discrimination. British Caribbean Americans who endorsed greater agreement with horizontal individualism were less likely to perceive racial discrimination. The same worldview was unrelated to African Americans' perceptions of racial discrimination. The results are discussed with respect to within-group heterogeneity among persons of African descent. Implications for counseling persons of African descent and future research directions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献