Recognition of 3D facial expression dynamics

In this paper we propose a method that exploits 3D motion-based features between frames of 3D facial geometry sequences for dynamic facial expression recognition. An expressive sequence is modelled to contain an onset followed by an apex and an offset. Feature selection methods are applied in order to extract features for each of the onset and offset segments of the expression. These features are then used to train GentleBoost classifiers and build a Hidden Markov Model in order to model the full temporal dynamics of the expression. The proposed fully automatic system was employed on the BU-4DFE database for distinguishing between the six universal expressions: Happy, Sad, Angry, Disgust, Surprise and Fear. Comparisons with a similar 2D system based on the motion extracted from facial intensity images was also performed. The attained results suggest that the use of the 3D information does indeed improve the recognition accuracy when compared to the 2D data in a fully automatic manner.     

Hop distance–based bandwidth allocation technique for elastic optical networks

Elastic optical networks (EON) have emerged as a solution to the growing needs of the future internet, by allowing for greater flexibility, spectrum efficiency, and scalability, when compared to WDM solutions. EONs achieve those improvements through finer spectrum allocation granularity. However, due to the continuity and contiguity constrains, distant connections that are routed through multiple hops suffer from increased bandwidth blocking probability (BBP), while more direct connections are easier to form. This paper proposes HopWindows, a novel method that strategically allocates bandwidth to connections based on their hop distance. This new algorithm applies masks that control the range of frequency slots (FSs) allocated to each n‐hop connection. Furthermore, a new network metric is introduced, the normalized bandwidth blocking probability (normalized BBP). Utilization of this metric ensures increased fairness to distant connections. Extended simulation results are presented which indicate that the proposed HopWindows method achieves a superior performance over the well‐known FirstFit algorithm. The proposed algorithm may achieve a decrease in bandwidth blocking probability of up to 50%.     

White and grey matter development in utero assessed using motion-corrected diffusion tensor imaging and its comparison to ex utero measures

Objective

Fetal brain diffusion tensor imaging (DTI) offers quantitative analysis of the developing brain. The objective was to 1) quantify DTI measures across gestation in a cohort of fetuses without brain abnormalities using full retrospective correction for fetal head motion 2) compare results obtained in utero to those in preterm infants.

Materials and methods

Motion-corrected DTI analysis was performed on data sets obtained at 1.5T from 32 fetuses scanned between 21.29 and 37.57 (median 31.86) weeks. Results were compared to 32 preterm infants scanned at 3T between 27.43 and 37.14 (median 33.07) weeks. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were quantified by region of interest measurements and tractography was performed.

Results

Fetal DTI was successful in 84% of fetuses for whom there was sufficient data for DTI estimation, and at least one tract could be obtained in 25 cases. Fetal FA values increased and ADC values decreased with age at scan (PLIC FA: p = 0.001; R² = 0.469; slope = 0.011; splenium FA: p < 0.001; R² = 0.597; slope = 0.019; thalamus ADC: p = 0.001; R² = 0.420; slope = − 0.023); similar trends were found in preterm infants.

Conclusion

This study demonstrates that stable DTI is feasible on fetuses and provides evidence for normative values of diffusion properties that are consistent with aged matched preterm infants.

     

Translating N‐Glycan Analytical Applications into Clinical Strategies for Ovarian Cancer

Protein glycosylation, particularly N‐linked glycosylation, is a complex posttranslational modification (PTM), which plays an important role in protein folding and conformation, regulating protein stability and activity, cell–cell interaction, and cell signaling pathways. This review focuses on analytical techniques, primarily MS‐based techniques, to qualitatively and quantitatively assess N‐glycosylation while successfully characterizing compositional, structural, and linkage features with high specificity and sensitivity. The analytical techniques explored in this review include LC–ESI–MS/MS and MALDI time‐of‐flight MS (MALDI‐TOF‐MS), which have been used to analyze clinical samples, such as serum, plasma, ascites, and tissue. Targeting the aberrant N‐glycosylation patterns observed in MALDI–MS imaging (MSI) offers a platform to visualize N‐glycans in tissue‐specific regions. The studies on the intra‐patient (i.e., a comparison of tissue‐specific regions from the same patient) and inter‐patient (i.e., a comparison of tissue‐specific regions between different patients) variation of early‐ and late‐stage ovarian cancer (OC) patients identify specific N‐glycan differences that improve understanding of the tumor microenvironment and potentially improve therapeutic strategies for the clinic.     

Précis: from unstructured keywords as queries to structured databases as answers

Précis queries represent a novel way of accessing data, which combines ideas and techniques from the fields of databases and information retrieval. They are free-form, keyword-based, queries on top of relational databases that generate entire multi-relation databases, which are logical subsets of the original ones. A logical subset contains not only items directly related to the given query keywords but also items implicitly related to them in various ways, with the purpose of providing to the user much greater insight into the original data. In this paper, we lay the foundations for the concept of logical database subsets that are generated from précis queries under a generalized perspective that removes several restrictions of previous work. In particular, we extend the semantics of précis queries considering that they may contain multiple terms combined through the AND, OR, and NOT operators. On the basis of these extended semantics, we define the concept of a logical database subset, we identify the one that is most relevant to a given query, and we provide algorithms for its generation. Finally, we present an extensive set of experimental results that demonstrate the efficiency and benefits of our approach.     

In situ combustion synthesis of structured Cu-Ce-O and Cu-Mn-O catalysts for the production and purification of hydrogen

The combustion method was employed for the in situ synthesis of nanocrystalline Cu-Ce-O and Cu-Mn-O catalyst layers on Al metal foam, without the need of binder or additional calcination steps. Copper-manganese spinel oxides have been proposed as a catalytic system for hydrogen production via methanol steam reforming, while CuO-CeO₂ catalysts have been successfully examined for CO removal from reformed fuels via selective oxidation. In this work, the performance of these catalysts supported on Al metal foam has been investigated in the reactions of methanol reforming and selective CO oxidation. The Cu-Ce-O foam catalyst exhibited similar catalytic performance to the one of the powder catalyst in the selective oxidation of CO. The performance of the Cu-Mn-O foam catalyst in the steam reforming of methanol was inferior to the one of the powder catalyst at intermediate conversion levels, but almost complete conversion of methanol was obtained at the same temperature with both foam and powder catalysts.     

Chain conformational transformations in syndiotactic polypropylene/layered silicate nanocomposites during mechanical elongation and thermal treatment

Polymer nanocomposites prepared by melt-mixing syndiotactic polypropylene (sPP) with a quaternary modified montmorillonite have been studied with FT-IR and XRD spectroscopic techniques. FT-IR spectroscopic analysis has shown that the addition of the nanoclay results in a higher helical content for the syndiotactic polypropylene matrix. Furthermore, FT-IR spectroscopy showed that the presence of the nanoclay hinders the polymeric chains from achieving the degree of transformation from helical to trans-planar form during the application of mechanical stress compared to the neat sPP case. Accordingly, the sPP nanocomposites show a higher tendency relative to neat sPP to return to the initial helical conformation upon either releasing the applied mechanical tension or upon exposing to heat at 120 °C. Additionally, XRD patterns provided evidence that the use of low concentration of nanoclay (1%) resulted in partially exfoliated nanocomposites, while only intercalated nanostructures were produced at high nanoclay contents (10%). However, the application of stress can improve the degree of exfoliation of an sPP nanocomposite. In addition, linear dichroic infrared measurements which allow the monitoring of the influence of the nanoclay on the orientation of the polymeric chains during the application of stress showed that the trans-planar infrared bands exhibit lower orientation in comparison to the same bands in neat sPP, while the addition of nanoclay has no particular influence on the orientation of the infrared bands that are related to helical conformations. Finally, dynamic mechanical analysis (DMA) verified the enhanced mechanical properties of the sPP nanocomposites relative to neat sPP, whereas differential scanning calorimetry (DSC) depicted a slight increase in the glass transition temperature of the polymeric matrix in these nanocomposites, especially for low clay concentrations.     

Ultra‐low voltage fractional‐order circuits using current mirrors

Fractional‐order blocks, including differentiators, lossy and lossless integrators as well as filters of order 1 + a (0 < a < 1), are presented in this paper. The proposed topologies offer the benefit of ultra low‐voltage operation; in addition, reduced circuit complexity is achieved compared to the corresponding companding schemes, which have been already introduced in the literature. The ultra‐low voltage operation is performed through the employment of metal oxide semiconductor transistors biased in the subthreshold region. The reduction of circuit complexity is achieved through the utilization of current mirrors as active elements for realizing the required building blocks. The performance of the proposed fractional‐order circuits has been evaluated through the Analog Design Environment of the Cadence software and the design kit provided by the Taiwan Semiconductor Manufacturing Company (TSMC) 180 nm complementary metal oxide semiconductor process. Copyright © 2015 John Wiley & Sons, Ltd.     

Classification of simulated hyperplastic stages in the breast ducts based on ultrasound RF echo

Visual inspection of ultrasound is diagnostically limited for characterizing breast tissue, in particular when it comes to visually detecting hyperplasia that forms in the ducts at its early formation (at submillimeter resolution) stages. It can, of course, be seen using biopsies. But this will not be done unless the areas have been flagged using noninvasive modalities. The aim of this paper is to draw to the attention of the medical community (albeit through simulations) that the continuous wavelet transform decomposition (CWTD) that was proven in vivo for tissue characterization before has the potential to flag out simulated hyperplasia data at submillimeter resolutions. And it might be an excellent candidate for detecting in vivo hyperplastic changes in the breast. To the best of our knowledge, this is the first attempt at studying the potential of detecting cell growth in breast ducts using ultrasound. The stochastic decomposition model (the CWTD) of the RF echo with its coherent and diffuse components, yields image parameters that correlate closely with the structural parameters of the (simulated) hyperplastic stages of the breast tissue. The discrimination power of the various parameters is studied under a host of conditions, such as varying resolution, depth, and coherent to diffuse energy ratio (CDR) values using a point-scatterer model simulator that mimics epithelium hyperplastic growth in the breast ducts. These are shown to be useful for detecting the various types of simulated hyperplastic data. Careful analysis shows that three parameters, in particular the number of coherent scatterers, the Rayleigh scattering degree, and the energy of the diffuse scatterers, are most sensitive to variations in the hyperplastic simulated data. And they show very high ability to discriminate between various stages of simulated hyperplasia, even in cases of low resolution and low CDR values. Using the area under the receiver operating characteristics (ROC) curve (A(z)) as the performance metric, values of A(z) > 0.942 are obtained when discriminating between stages for resolution 0.948 for different duct densities.     

食品安全与包装材料的阻隔性

随着现代科学和技术的发展,包装材料发生了由传统到现代的演变。现代包装除了作为产品的容器,有合理尺寸、形状、方便使用外,作为产品安全的第一道防线,还需要提供必要的阻隔性和整体密封性,以满足保质期要求以及必要的物理强度,并经受运输过程可能面临的任何情况。传统的包装材料均为非渗透性,如玻璃、金属,或高渗透性,如纸张。现代包装材料主要是高分子复合材料,而所有的塑料都能被气体或水汽渗透。对于玻璃和金属等非渗透材料来说,可能泄漏的路径有接缝和瓶盖界面而渗透材质光考虑可能泄漏路径接缝、接口等是不够的。