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291.
W. A. C. Fernando 《Multimedia Tools and Applications》2006,28(3):301-320
This paper addresses an important area in video processing, namely compressed domain processing. For video indexing, video
scene transition detection is an essential step to segment the video. Current techniques for scene change detection tend to
suffer from a major limitation as most of them cannot identify scene transitions in the compressed domain. Since most video
is expected to be stored in the compressed domain, scene transition detection in this domain is highly desirable. In this
paper an algorithm for video scene change detection is proposed to overcome this limitation. In this scheme, properties of
the B-frames are used as it is capable of measuring the correlation between two adjacent reference frames. The results show
that this scheme performs better than schemes based on P-frames. Proposed scheme can be directly applied with compressed data
with minimum decompression and hence it is computationally efficient and makes real time implementations possible. Results
show that video scene transitions can be identified satisfactorily with the proposed scheme. 相似文献
292.
Celso M. Ogawa Kurt Faltin Fernando A. Maeda Cristina L. F. Ortolani Renata O. Guar Cristiane A. B. Cardoso Andr L. F. Costa 《Microscopy research and technique》2020,83(8):928-936
This study was undertaken to assess in vivo the corrosion in two commercial nickel–titanium (NiTi) orthodontic archwires removed from the oral cavity of patients using fluoride mouthwashes. Five volunteers took part in this study on the corrosion behavior of two brands of NiTi archwires (3M and AO (brand of archwire)) during use of two mouthwashes with neutral sodium fluoride 1.1%, one with acidulated fluoride 1.1%, and one with placebo and a control group. Each patient used one mouthwash in three different periods of time for 1 min a day for 30 days. The archwires were assessed with scanning electron microscopy and atomic force microscopy for qualitative and quantitative analysis. The values obtained with atomic force microscopy (AFM) were submitted to normality test, two‐way analysis of variance, and Tukey's test at a significance level of 5%. The AFM images showed a gradual qualitative increase in the roughness of both types of wire between the treatments: control < placebo < neutral fluoride < acidulated fluoride. The arithmetic average of the roughness and root mean square of the roughness were similar. As for 3M archwires, only the acidulated fluoride group differed statistically from the others. As for AO archwires, the control and placebo groups did not differ from each other, but differed from the other fluoride treatments. The group using neutral fluoride also differed significantly from the acidulated fluoride group. 3M archwires were not affected by daily oral challenges. AO archwires were not affected by daily oral challenges either; their association with fluoride, either neutral or acidulated, increased their roughness. 相似文献
293.
Elizandra Silva da Penha Rogrio Lacerda‐Santos Luanna Abílio Diniz Melquíades de Medeiros Rosana Araújo Rosendo Antonielson dos Santos Marcus Vinícius Lia Fook Wladymyr Jefferson Bacalhau de Sousa Millena de Oliveira Firmino Erik Montagna 《Microscopy research and technique》2020,83(10):1208-1216
The focus of this triple‐blind study was on evaluating the effect of chitosan combined with Dysphania ambrosioides (A) extract on the bone repair process in vivo. In total, 60 male Wistar rats (Rattus norvegicus albinus) weighing between 260 and 270 g were randomly selected for this study and distributed into four groups (n = 15). Group C (chitosan), Group CA5 (chitosan + 5% of D. ambrosioides), Group CA20 (chitosan + 20% of D. ambrosioides), and Group CO (Control‐Blood clot). In each animal, bone defects measuring 2 mm in diameter were performed in both tibias for placement of the substances. After 7, 15, and 30 days, the animals were sedated and sacrificed using the cervical dislocation technique and the tissues were analyzed under optical microscope relative to the following events: inflammatory infiltrate, necrosis, osteoclasts, osteoblasts, fibroblasts, periosteal, and endosteal bone formation. The data were evaluated to verify distribution using the Kolmogorov–Smirnov test, and variance, using the Levene test; as distribution was not normal, data were subjected to the Kruskal–Wallis and Dunn nonparametric tests (p < .05). A significant inflammatory infiltrate was observed in Group CA5 (p = .008) in the time interval of 7 days, and in Group C at 15 (p = .009) and 30 (p = .017) days. Osteoblastic activity was more significant in Group CA20 (p = .027) compared with CA5 in the time interval of 7 days. Group CA20 demonstrated a significantly higher endosteal and periosteal bone formation value in the time interval of 7 (p = .013), 15 (p = .004), and 30 days (p = .008) compared with the other groups. The null hypothesis was refuted, bone regeneration was faster in spheres with an association of chitosan and 20% extract, and complete bone repair occurred clinically at 15 days and histologically at 30 days. The spheres proved to be a promising method for the biostimulation of alveolar bone repair and bone fractures. 相似文献
294.
Anauara L. e Silva Lucas E. de Lima Terceiro Matheus F. de Lima Rafael Costa‐Silva Ednalva A. V. dos Santos Maria de Ftima Agra 《Microscopy research and technique》2020,83(3):287-296
Micromorphological studies were carried out using multiple microscopic techniques on the leaves and stem bark of Byrsonima sericea DC. (Malpighiaceae), a species popularly known as “murici” and used medicinally, in order to identify both qualitative and quantitative features of leaf and stem anatomy and histochemistry as differential parameters to support both the quality control of its ethnodrugs and the taxonomy of the genus. The study was conducted using traditional techniques of plant anatomy, histochemical tests, and the stomatal index (SI). Byrsonima sericea has hypostomatic leaves, anomocytic stomata, and its epidermal walls are anticlinal and straight on the adaxial and curved on the abaxial faces. T‐shaped trichomes were observed mainly on the abaxial surface. The leaf epidermis showed waxes syntopism on both surfaces, with the occurrence of different crystalloid forms on a single phylloplane. The mesophyll is dorsiventral, with 3‐4 collateral vascular bundles. Phenolic compounds, starch, and proteins were identified in the petiole and stem. The SI was 14.5 ± 0.53% (p < .05), but did not showed significant variations. A set of characters were found to be distinctive for the studied species, however, constituting parameters that could be used to separate B. sericea from other species of the genus. 相似文献
295.
Rodrigo F. P. Martins Arman Ahnood Nuno Correia Luís M. N. P. Pereira Raquel Barros Pedro M. C. B. Barquinha Ricardo Costa Isabel M. M. Ferreira Arokia Nathan Elvira E. M. C. Fortunato 《Advanced functional materials》2013,23(17):2153-2161
The ability to process and dimensionally scale field‐effect transistors with and on paper and to integrate them as a core component for low‐power‐consumption analog and digital circuits is demonstrated. Low‐temperature‐processed p‐ and n‐channel integrated oxide thin‐film transistors in the complementary metal oxide semiconductor (CMOS) inverter architecture are seamlessly layered on mechanically flexible, low‐cost, recyclable paper substrates. The possibility of building these circuits using low‐temperature processes opens the door to new applications ranging from smart labels and sensors on clothing and packaging to electronic displays printed on paper pages for use in newspapers, magazines, books, signs, and advertising billboards. Because the CMOS circuits reported constitute fundamental building blocks for analog and digital electronics, this development creates the potential to have flexible form factor computers seamlessly layered onto paper. The holistic approach of merging low‐power circuitry with a recyclable substrate is an important step towards greener electronics. 相似文献
296.
Jacobina C.B. Oliveira T.M. da Silva E.R.C. 《Industrial Electronics, IEEE Transactions on》2006,53(2):467-476
This paper investigates the control of a single-phase three-leg ac/ac reversible converter in which a leg is shared by both the grid and the load side. Pulsewidth-modulation (PWM) techniques based on scalar and vector approaches are developed, introducing the concept of local and general apportioning factor and, also, a complete equivalence between scalar and space vector PWM. A hysteresis current controller capable of taking into account the shared leg is developed and a zero current error linear controller is presented. Furthermore, a control strategy to obtain maximum utilization of the dc-bus voltage is proposed. In addition, several relevant characteristics of the converter are addressed, such as voltage rating, harmonic distortion, shared leg and capacitor currents, and power rating. The converter is compared to four-leg and two-leg converters. Experimental results are presented. 相似文献
297.
Antônio Alisson Alencar Freitas Fernando Lessa Tofoli Edilson Mineiro Sá Junior Sergio Daher Fernando Luiz Marcelo Antunes 《International Journal of Electronics》2016,103(5):898-912
A high voltage step-up nonisolated DC–DC converter based on coupled inductors suitable to photovoltaic (PV) systems applications is proposed in this paper. Considering that numerous approaches exist to extend the voltage conversion ratio of DC–DC converters that do not use transformers, a detailed comparison is also presented among the proposed converter and other popular topologies such as the conventional boost converter and the quadratic boost converter. The qualitative analysis of the coupled-inductor-based topology is developed so that a design procedure can be obtained, from which an experimental prototype is implemented to validate the theoretical assumptions. 相似文献
298.
Jack bean (Canavalia ensiformis) starch is composed of granules measuring up to 37 micra. Gelatinization temperatures of the granules range from 67.5 to 78 °C. Its pastes, in concentrations up to 6 % did not show swelling peak which appears only in high concentrations. They are very stable during stirring, both at low and high temperatures. They are also more resistant to α-amylase bacterial action than those of corn starch. The results, both for granules and pastes of this starch, show a great resemblance with the same data for guandu bean. 相似文献
299.
Thamires Rodrigues de Sousa Beatriz Oliveira Fagundes Andrezza Nascimento Lorena Abreu Fernandes Fbio da Ressureio Sgnotto Raquel Leo Orfali Valria Aoki Alberto Jos da Silva Duarte Sabri Saeed Sanabani Jefferson Russo Victor 《International journal of molecular sciences》2022,23(12)
Atopic dermatitis (AD) is a common relapsing inflammatory skin disorder characterized by immune-mediated inflammation and epidermal barrier dysfunction. The pathogenesis of AD is multifactorial and has not been fully elucidated to date. This study aimed to evaluate whether serum IgG from adult AD patients could modulate the thymic maturation of IL-22-producing T cells and CLA+ T cells of non-atopic infants. Given that miRNAs regulate immune response genes, we evaluated whether miRNA expression is also altered in cultured thymocytes. Thymocytes were cultured with purified IgG from AD patients or control conditions (mock, Intravenous-IgG (IVIg), non-atopic IgG, or atopic non-AD IgG). Using flow cytometry analysis, we assessed the expression of CLA and intracellular levels of IL-4, IFN-γ, and IL-22 on double-positive T cells (DP T), CD4 T cells, or CD8 T cells. We also investigated the frequency of IgG isotypes and their direct interaction with the thymic T cells membrane. The miRNA profiles were evaluated by the Illumina small RNA-seq approach. MiRNA target gene prediction and enrichment analyses were performed using bioinformatics. Increased frequencies of IL-22 and CLA+ producing CD4+ T cells cultured with IgG of AD patients was seen in non-atopic infant thymocytes compared to all control conditions. No alterations were observed in the frequency of IgG isotypes among evaluated IgG pools. Evidence for a direct interaction between IgG and thymic DP T, CD4 T, and CD8 T cells is presented. The small RNA-seq analysis identified ten mature miRNAs that were modulated by AD IgG compared to mock condition (miR-181b-5p, hsa-miR-130b-3p, hsa-miR-26a-5p, hsa-miR-4497, has-miR-146a, hsa-let-7i-5p, hsa-miR-342-3p, has-miR-148a-3p, has-miR-92a and has-miR-4492). The prediction of the targetome of the seven dysregulated miRNAs between AD and mock control revealed 122 putative targets, and functional and pathway enrichment analyses were performed. Our results enhance our understanding of the mechanism by which IgG can collaborate in thymic T cells in the setting of infant AD. 相似文献
300.
Matilde Ortiz-Gonzalez Ignacio Prez-Victoria Inmaculada Ramirez-Macias Nuria de Pedro Angel Linde-Rodriguez Víctor Gonzlez-Menndez Victoria Sanchez-Martin Jesús Martín Ana Soriano-Lerma Olga Genilloud Virginia Perez-Carrasco Francisca Vicente Jos Maceira Carlos A. Rodrígues-Poveda Jos María Navarro-Marí Fernando Reyes Miguel Soriano Jose A. Garcia-Salcedo 《International journal of molecular sciences》2022,23(11)