Science macro-indicators: some aspects of ost experience

We report OST experience on macro-indicators producing, especially on academic science and ISI sources. This task requires a combination of organizational choices for data handling and processing, and of bibliometric choices for a selection of indicators appropriate to the missions. Both aspects are briefly studied: the OST database, which also contains nonbibliometric datasets, is organized on the relational principle (RDBMS). Bibliometric indicators selected are classical ones, with a stress on overall coherence. In conclusion, standardization issue is briefly discussed. Standardization may not be desirable at the same extent for different targets (data, nomenclatures, indicators, procedures, etc.) and must not hinder further research. Natural process of communication and explication may also lead to fruitful convergences, without freezing supposed best ways.     

Axonal excitability and motor propagation velocity of peripheral nerves in patients with acute vascular lesions of the brain

From measurements of maximum and minimum motor nerve propagation velocity and neuronal excitability we conclude that there is a functional loss of motor units and distal nerve "dying back" in persons affected with unilateral acute cerebral vascular lesions. The study also suggests that transynaptic degeneration affects the lower motor neurone function on both sides.     

Near-Complete Remission of Glioblastoma in a Patient Treated with an Allogenic Dendritic Cell-Based Vaccine: The Role of Tumor-Specific CD4+T-Cell Cytokine Secretion Pattern in Predicting Response and Recurrence

Immunotherapy has brought hope to the fight against glioblastoma, but its efficacy remains unclear. We present the case of CST, a 25-year-old female patient with a large right-hemisphere glioblastoma treated with a dendritic–tumor cell fusion vaccine. CST showed a near-complete tumor response, with a marked improvement in her functional status and simultaneous increases in tumor-specific CD8+ and CD4+ T cells. Two months before recurrence, the frequency of tumor-specific T cells decreased, while that of IL-17 and CD4+ T cells increased. CST passed away 15 months after enrollment. In this illustrative case, the tumor-specific CD4+ T-cell numbers and phenotype behaved as treatment efficacy biomarkers, highlighting the key role of the latter in glioblastoma immunotherapy.     

A Guide to Polysaccharide-Based Hydrogel Bioinks for 3D Bioprinting Applications

Three-dimensional (3D) bioprinting is an innovative technology in the biomedical field, allowing the fabrication of living constructs through an approach of layer-by-layer deposition of cell-laden inks, the so-called bioinks. An ideal bioink should possess proper mechanical, rheological, chemical, and biological characteristics to ensure high cell viability and the production of tissue constructs with dimensional stability and shape fidelity. Among the several types of bioinks, hydrogels are extremely appealing as they have many similarities with the extracellular matrix, providing a highly hydrated environment for cell proliferation and tunability in terms of mechanical and rheological properties. Hydrogels derived from natural polymers, and polysaccharides, in particular, are an excellent platform to mimic the extracellular matrix, given their low cytotoxicity, high hydrophilicity, and diversity of structures. In fact, polysaccharide-based hydrogels are trendy materials for 3D bioprinting since they are abundant and combine adequate physicochemical and biomimetic features for the development of novel bioinks. Thus, this review portrays the most relevant advances in polysaccharide-based hydrogel bioinks for 3D bioprinting, focusing on the last five years, with emphasis on their properties, advantages, and limitations, considering polysaccharide families classified according to their source, namely from seaweed, higher plants, microbial, and animal (particularly crustaceans) origin.     

Delay sensing for long-term variations and defects monitoring in safety–critical applications

The impact of parametric variations on digital circuit performance is increasing in nanometer Integrated Circuits (IC), namely of Process, power supply Voltage and Temperature (PVT) variations. Moreover, circuit aging also impacts circuit performance, especially due to Negative Bias Temperature Instability (NBTI) effect. A growing number of physical defects manifest themselves as delay faults (at production, or during product lifetime). On-chip, on-line delay monitoring, as a circuit failure prediction technique, can be an attractive solution to guarantee correct operation in safety–critical applications. Safe operation can be monitored, by predictive delay fault detection. A delay monitoring methodology and a novel delay sensor (to be selectively inserted in key locations in the design and to be activated according to user’s requirements) is proposed, and a 65 nm design is presented. The proposed sensor is programmable, allowing delay monitoring for a wide range of delay values, and has been optimized to exhibit low sensitivity to PVT and aging-induced variations. Two MOSFET models—BPTM and ST—have been used. As abnormal delays can be monitored, regardless of their origin, both parametric variations and physical defects impact on circuit performance can be identified. Simulation results show that the sensor is effective in identifying such abnormal delays, due to NBTI-induced aging and to resistive open defects.     

All-Optical Vestigial Sideband Generation Using a Semiconductor Optical Amplifier

An all-optical setup to generate vestigial sideband signals based on self-phase modulation in a semiconductor optical amplifier is experimentally demonstrated at 10 Gb/s. Sideband suppressions higher than 15 dB are reported with improved eye opening. Wavelength-independent operation over 26 nm is demonstrated. Increased chromatic dispersion tolerance is verified: a receiver sensitivity penalty of 5.3 dB, relative to back-to-back, is obtained after transmission over 2720 ps/nm; whereas conventional double sideband is penalized by 4.0 dB after 1360 ps/nm     

Metrics and Criteria for Quality Assessment of Testable Hw/Sw Systems Architectures

The purpose of this paper is to present a novel methodology for assessing the quality of architecture solutions of hw/sw systems, with particular emphasis on testability. Criteria and metrics for quality assessment are proposed and used to assist the design team in selecting a best-fitted architecture that satisfies not only functional requirements, but also test requirements. The methodology makes use of object-oriented modeling techniques. Near-optimum clustering of methods and attributes into objects is carried out, in such a way that objects with moderate complexity, low coupling and high functional autonomy, result. The main features of the methodology are ascertained through a case study.     

Automatic adjustment of a medical imaging data acquisition system to unknown delays in the input communication channels

In this article, novel FIFO and RAM-based Synchronization Modules to keep synchronism throughout the input channels of a Data Acquisition Electronics (DAE) system are proposed. DAE is a main component of a Medical Imaging System, namely, a Positron Emission Mammography (PEM) system. DAE input data comes from a scanner constituted by an array of scintillating crystals. The scanner captures radiation generated by human cells injected with a radioactive substance and converts it into electrical signals. The corresponding digital information is sent to the DAE. In order to deal with the huge amount of data, flowing at high data rates, point-to-point (p2p) communication channels are used between the scanner and the DAE. Propagation delays associated with the different communication channels may change differently. Additionally, differences among channel delays may exceed one clock period. Keeping synchronism in these circumstances requires more than the classical asynchronous FIFO solution. All these aspects motivate the work proposed in this article. The PEM DAE system is a multi-board, multi-FPGA, multi-clock domain system. Therefore, the DAE architecture follows a Globally Asynchronous, Locally Synchronous (GALS) design style. The novel Synchronization Modules proposed in this article are implemented in the DAE. The effectiveness of these new structures is validated through simulation and laboratorial test. Simulation and test results are presented.     

Domain-overriding and digital filtering for 3-D FDTD subgridded simulations

We report on an extension of finite-difference time-domain (FDTD) subgridding (SG) algorithms incorporating digital filters and domain-overriding to three-dimensional (3-D) simulations and to problems involving materials traversing the SG interfaces. We show that significant improvements in accuracy can be obtained for these cases as well.