Hypermedia authoring tools based on OLE technology

This paper report on recent and on going work related to the design of a set of hypermedia authoring tools intended to produce courseware, to be used for self learning or distance learning and training environments in a cooperative way. These tools have roots in a standalone hypermedia editor developed to create courseware, to which were added other tools to enhance its usability, namely a hypermedia player to view courseware in self study mode, and a hypermedia browser to create, to navigate and to display graphically the hypermedia document structure. The underlying metaphors are the overhead projector, the transparency and the layer. This system was developed for the MS-Windows environment, supporting OLE technology. We discuss the impact that such technology might have on the look and feel of hypermedia learning material and we describe the implementation of a Hypermedia Editor, Browser and Player tools.Part of this work is carried out in the context of the Co-Learn European project, which is aiming to design and to implement a third generation cooperative learning environment.     

Oil shale solid waste recycling in the development of new silica fillers for elastomeric composites

The production of Brazilian shale oil gives rise to 6600 ton/day of a solid waste of retorted shale, and larger amounts of dolomitic waste rock are generated during mining. Two vitreous materials were obtained through the melting of different proportions of these two wastes. By leaching these materials with hydrochloric acid at 90°C, two different kinds of silicas (powder and gel, both amorphous) with specific surface areas reaching up to ～ 420 m²/g were generated. These silicas were further modified through an Ostwald‐ripening type of treatment in ammonium hydroxide solution at 80°C. The process eliminated almost completely the deleterious micropores. The obtained silicas were evaluated as reinforcing fillers for SBR‐1502. The employment of one of the modified silicas gave rise to a composite with better mechanical properties than those displayed by the one with untreated silica. Scanning electronic microscopic observation disclosed the existence of great morphological differences between these silicas. Apparently, the aging treatment gave rise to the production of better anchoring sites for the elastomer molecules. NMR studies also showed the reduction of the silanol content of the treated silica. The fracture surface of the composite disclosed a good wetting of this silica by the elastomeric matrix. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2856–2867, 2001     

Dissemination of Enterococcus faecalis and Enterococcus faecium in a Ricotta Processing Plant and Evaluation of Pathogenic and Antibiotic Resistance Profiles

In this work, the sources of contamination by Enterococcus spp. in a ricotta processing line were evaluated. The isolated strains were tested for virulence genes (gelE, cylA,B, M, esp, agg, ace, efaA, vanB), expression of virulence factors (hemolysin and gelatinase), and the resistance to 10 different antibiotics. Enterococcus faecium and Enterococcus faecalis were subjected to discriminatory identification by intergenic spacer region (ITS)‐polymerase chain reaction and sequencing of the ITS region. The results showed that Enterococcus spp. was detected in the raw materials, environment samples and the final product. None of the 107 Enterococcus isolates were completely free from all virulence genes considered. A fraction of 21.5% of the isolates containing all of the genes of the cylA, B, M operon also expressed β‐hemolysis. Most of the isolates showed the gelE gene, but only 9.3% were able to hydrolyze gelatin. In addition, 23.5% of the observed Enterococcus isolates had the vanB gene but were susceptible to vancomycin in vitro. The dissemination of antibiotic‐resistant enterococci was revealed in this study: 19.3% of the E. faecium samples and 78.0% of the E. faecalis samples were resistant to at least one of the antibiotics tested. Sequencing of region discriminated 5 and 7 distinct groups among E. faecalis and E. faecium, respectively. Although some similarity was observed among some of the isolates, all E. faecalis and E. faecium isolates had genetic differences both in the ITS region and in the virulence profile, which makes them different from each other.     

Cumene hydrocracking and thiophene HDS on niobia-supported Ni, Mo and Ni–Mo catalysts

Results are reported on the XPS characterization and catalytic activity in cumene hydrocracking (2.8 MPa, 623 K) and thiophene HDS (2.8 MPa, 523–573 K) of sulfided Ni, Mo and Ni–Mo catalysts supported on alumina and on pure and phosphated niobia. From the XPS results, evidence was obtained for the formation of a surface niobium sulfide with stoichiometry close to NbS₂ during catalyst sulfidation. Sintering of supported nickel during sulfidation occurred to a much smaller extent with the niobia-supported catalysts than with the alumina-supported ones. The dispersion of alumina-supported molybdenum was little influenced by sulfidation, whereas, with the niobia supports, the molybdenum surface concentration increased with sulfidation. With the alumina support, the Ni–Mo combination caused the dispersion of the sulfided nickel to be improved, possibly due to formation of a NiMoS phase. This was not observed with the niobia-supported catalysts.

Reasonable linear correlations were also found between the intrinsic activity for cumene hydrocracking and the amount of sulfided niobium in the catalysts, but the catalysts supported on phosphated niobia had a higher intrinsic activity than the ones supported on pure niobia. In thiophene HDS, the activity of the niobia-supported nickel catalysts was much larger than the activity of the alumina-supported ones. The activity of the niobia-supported molybdenum catalysts was smaller than that of the alumina-supported catalyst. With the bimetallic catalysts, little or no synergy was observed with the niobia-supported catalysts, in sharp contrast with the alumina case.     

CD146+ Pericytes Subset Isolated from Human Micro-Fragmented Fat Tissue Display a Strong Interaction with Endothelial Cells: A Potential Cell Target for Therapeutic Angiogenesis

Pericytes (PCs) are mesenchymal stromal cells (MSCs) that function as support cells and play a role in tissue regeneration and, in particular, vascular homeostasis. PCs promote endothelial cells (ECs) survival which is critical for vessel stabilization, maturation, and remodeling. In this study, PCs were isolated from human micro-fragmented adipose tissue (MFAT) obtained from fat lipoaspirate and were characterized as NG2⁺/PDGFRβ⁺/CD105⁺ cells. Here, we tested the fat-derived PCs for the dispensability of the CD146 marker with the aim of better understanding the role of these PC subpopulations on angiogenesis. Cells from both CD146-positive (CD146⁺) and negative (CD146⁻) populations were observed to interact with human umbilical vein ECs (HUVECs). In addition, fat-derived PCs were able to induce angiogenesis of ECs in spheroids assay; and conditioned medium (CM) from both PCs and fat tissue itself led to the proliferation of ECs, thereby marking their role in angiogenesis stimulation. However, we found that CD146⁺ cells were more responsive to PDGF-BB-stimulated migration, adhesion, and angiogenic interaction with ECs, possibly owing to their higher expression of NCAM/CD56 than the corresponding CD146⁻ subpopulation. We conclude that in fat tissue, CD146-expressing cells may represent a more mature pericyte subpopulation that may have higher efficacy in controlling and stimulating vascular regeneration and stabilization than their CD146-negative counterpart.     

Mechanical and chemical properties of poly(styrene‐isobutylene‐styrene) block copolymers: Effect of sulfonation and counter ion substitution

In this study, the mechanical and chemical properties of a series of sulfonated poly(styrene‐isobutylene‐styrene) (SIBS) block copolymers were evaluated using a combination of nanoindentation, dynamic mechanical analysis (DMA), elemental analysis (EA), Fourier transform infrared spectroscopy (FTIR), water absorption, and small angle X‐ray scattering studies (SAXS). The materials properties were characterized as a function of the sulfonation percent in the block copolymers, as well as a result of the counter‐ion substitution with Mg²⁺, Ca²⁺, and Ba²⁺. Nanoindentation studies revealed that the elastic modulus (E) and hardness (H) increase with sulfonation up to a certain level, at which point, the effect of water content further hinders any mechanical reinforcement. The incorporation of counter‐ions increases E and H, but the results are dependent upon the size of the counter‐ion. DMA results showed that the polymer maintained the glass transition temperature (T_g) of the polyisobutylene (PIB) segment (?60°C) regardless of the sulfonation level or counter‐ion substituted. However, both the shoulder of the PIB T_g (?30°C), which was probably caused by a Rouse‐type motion, as well as the T_g of polystyrene (105°C) disappeared upon sulfonation. Counter‐ion substitution increased the storage modulus of the rubbery plateau, which is indicative of a stronger and more thermally stable crosslinked complex formation. Additional unique relaxations were observed with the counter‐ions, and could be attributed to the stretching/rotation of the S? O bond and the interaction of the cations with the oxygen in the sulfonic group. FTIR results also revealed a unique shifting of the asymmetric S? O band when counter‐ions were added. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40344.     

A reduced memory bandwidth and high throughput HDTV motion compensation decoder for H.264/AVC High 4:2:2 profile

This article presents the HP422-MoCHA: optimized Motion Compensation hardware architecture for the High 4:2:2 profile of H.264/AVC video coding standard. The proposed design focuses on real-time decoding for HDTV 1080p (1,920 × 1,080 pixels) at 30 fps. It supports multiple sample bit-width (8, 9, or 10 bits) and multiple chroma sub-sampling formats (4:0:0, 4:2:0, and 4:2:2) to provide enhanced video quality experience. The architecture includes an optimized sample interpolator that processes luma and chroma samples in two parallel datapaths and features quarter sample accuracy, bi-prediction and weighted prediction. HP422-MoCHA also includes a hardwired Motion Vector Predictor, supporting temporal and spatial direct predictions. A novel memory hierarchy implemented as a 3-D Cache reduces the frame memory access, providing, on average, 62% of bandwidth and 80% of clock cycles reduction. The design was implemented in a Xilinx Virtex-II PRO FPGA, and also in an ASIC with a TSMC 0.18 μm standard cells technology. The ASIC implementation occupies 102 K equivalent gates and 56.5 KB of on-chip SRAM in a 3.8 × 3.4 mm² area. It presents a power consumption of 130 mW. Both implementations reach a maximum operation frequency of ~100 MHz, being able to motion compensate 37 bi-predictive frames or 69 predictive fps. The minimum required frequency to ensure the real-time decoding for HD1080p at 30 fps is 82 MHz. Since HP422-MoCHA is the first Motion Compensation architecture for the High 4:2:2 profile found in the literature, a Main profile MoCHA was used for comparison purposes, showing the highest throughput among all presented works. However, the HP422-MoCHA architecture also reaches the highest throughput when compared with the other published Main profile MC solutions, even considering the significantly higher complexity of the High 4:2:2 profile.     

Blending Scrum practices and CMMI project management process areas

Software development organizations that have been employing capability maturity models, such as SW-CMM or CMMI for improving their processes are now increasingly interested in the possibility of adopting agile development methods. In the context of project management, what can we say about Scrum’s alignment with CMMI? The aim of our paper is to present the mapping between CMMI and the agile method Scrum, showing major gaps between them and identifying how organizations are adopting complementary practices in their projects to make these two approaches more compliant. This is useful for organizations that have a plan-driven process based on the CMMI model and are planning to improve the agility of processes or to help organizations to define a new project management framework based on both CMMI and Scrum practices.     

TTS-Portuguese Corpus: a corpus for speech synthesis in Brazilian Portuguese

Speech provides a natural way for human–computer interaction. In particular, speech synthesis systems are popular in different applications, such as personal assistants, GPS applications, screen readers and accessibility tools. However, not all languages are on the same level when in terms of resources and systems for speech synthesis. This work consists of creating publicly available resources for Brazilian Portuguese in the form of a novel dataset along with deep learning models for end-to-end speech synthesis. Such dataset has 10.5 h from a single speaker, from which a Tacotron 2 model with the RTISI-LA vocoder presented the best performance, achieving a 4.03 MOS value. The obtained results are comparable to related works covering English language and the state-of-the-art in European Portuguese.