SAR amplitude probability density function estimation based on a generalized Gaussian model.

In the context of remotely sensed data analysis, an important problem is the development of accurate models for the statistics of the pixel intensities. Focusing on synthetic aperture radar (SAR) data, this modeling process turns out to be a crucial task, for instance, for classification or for denoising purposes. In this paper, an innovative parametric estimation methodology for SAR amplitude data is proposed that adopts a generalized Gaussian (GG) model for the complex SAR backscattered signal. A closed-form expression for the corresponding amplitude probability density function (PDF) is derived and a specific parameter estimation algorithm is developed in order to deal with the proposed model. Specifically, the recently proposed "method-of-log-cumulants" (MoLC) is applied, which stems from the adoption of the Mellin transform (instead of the usual Fourier transform) in the computation of characteristic functions and from the corresponding generalization of the concepts of moment and cumulant. For the developed GG-based amplitude model, the resulting MoLC estimates turn out to be numerically feasible and are also analytically proved to be consistent. The proposed parametric approach was validated by using several real ERS-1, XSAR, E-SAR, and NASA/JPL airborne SAR images, and the experimental results prove that the method models the amplitude PDF better than several previously proposed parametric models for backscattering phenomena.     

CMOS Transconductors With Nearly Constant Input Ranges Over Wide Tuning Intervals

Three different bias strategies aimed to reduce the effect of tuning on either the differential input range or the common-mode range of triode-region CMOS transconductors are presented. The method is applied to an original transconductor topology that is optimized to produce ultralow G_m values. A prototype circuit, which was designed with the 0.35-mum bipolar-CMOS-DMOS (BCD6) process of STMicroelectronics, is presented. The effectiveness and limitations of the method are characterized by means of electrical simulations     

A comprehensive study on compositional and structural changes in 45S5 bioglass products exposed to simulated body fluid

The interaction of fully dense 45S5‐bioglass derived samples produced by Spark Plasma Sintering (SPS) with simulated body fluid (SBF) solution was investigated in detail taking advantage of the Rietveld refinement method to quantitatively evidence the corresponding microstructural and compositional changes. It is observed that, when the original amorphous nature is mostly (75 wt%) preserved in the material during sintering (550°C, 2 minutes), the resulting specimens dissolve faster and determine relatively higher pH increase and ions release in the SBF solution. Correspondingly, a relatively lower amount of hydroxycarbonate apatite (HCA) is formed on their surface. In contrast, a more extensive apatite layer with trabecular structure is generated within 3 days storage on the surface of fully crystallized samples obtained at 600°C by SPS, which only consists of Na–Ca silicate grains (20 nm). Moreover, as the sintering temperature and dwell time were increased to 700°C and 20 minutes, respectively, a rhenanite‐like phase was also formed (about 15 wt%), other than crystallites growth to 90 nm. Interestingly, the presence of rhenanite provides a beneficial contribution for the production of the HCA layer, which was found the largest for this system when considering storage periods of 7 and 14 days, respectively.     

Self organizing motor maps for color-mapped image re-indexing.

Palette re-ordering is an effective approach for improving the compression of color-indexed images. If the spatial distribution of the indexes in the image is smooth, greater compression ratios may be obtained. As is already known, obtaining an optimal re-indexing scheme is not a trivial task. In this paper, we provide a novel algorithm for palette re-ordering problem making use of a motor map neural network. Experimental results show the real effectiveness of the proposed method both in terms of compression ratio and zero-order entropy of local differences. Also, its computational complexity is competitive with previous works in the field.     

Alarmins as a Possible Target of Future Therapies for Atrial Fibrillation

To date, worldwide, atrial fibrillation is the most common cardiovascular disease in adults, with a prevalence of 2% to 4%. The trigger of the pathophysiological mechanism of arrhythmia includes several factors that sustain and exacerbate the disease. Ectopic electrical conductivity, associated with the resulting atrial mechanical dysfunction, atrial remodeling, and fibrosis, promotes hypo-contractility and blood stasis, involving micro endothelial damage. This causes a significant local inflammatory reaction that feeds and sustains the arrhythmia. In our literature review, we evaluate the role of HMGB1 proteins, heat shock proteins, and S100 in the pathophysiology of atrial fibrillation, offering suggestions for possible new therapeutic strategies. We selected scientific publications on the specific topics “alarmins” and “atrial fibrillation” from PubMed. The nonsystematic review confirms the pivotal role of molecules such as S100 proteins, high-mobility group box-1, and heat shock proteins in the molecular pattern of atrial fibrillation. These results could be considered for new therapeutic opportunities, including inhibition of oxidative stress, evaluation of new anticoagulant drugs with novel therapeutic targets, molecular and genetic studies, and consideration of these alarmins as predictive or prognostic biomarkers of disease onset and severity.     

Geomechanical design of a room and rib pillar granite mine

The geomechanical and stability design of an underground granite mine located in Canal San Bovo （Trento district, Northeastern Italy） was described. The exploitation of the granite, which is used in the ceramic industry, was carried out by the rooms and rib pillars method. The rooms are 12 m wide while the pillars are 11 m wide and they cross the main discontinuity set of the rock mass in the perpendicular direction. To verify the stability condition of an underground mine, it is necessary to carry out the calcula- tions that are able to check both the local and global stability of the rock mass. In the studied example, this approach has been applied with the development of analytical and numerical parametric analyses and it has permitted to get the best orientation and to design the size of rooms and pillars.     

Reactive navigation through multiscroll systems: from theory to real-time implementation

In this paper a new reactive layer for multi-sensory integration applied to robot navigation is proposed. The new robot navigation technique exploits the use of a chaotic system able to be controlled in real-time towards less complex orbits, like periodic orbits or equilibrium points, considered as perceptive orbits. These are subject to real-time modifications on the basis of environment changes acquired through a distributed sensory system. The strategy is inspired to the olfactory bulb neural activity observed in rabbits subject to external stimuli. The mathematical details of the approach are given including simulation results in a virtual environment. Furthermore the proposed strategy has been tested on an experimental environment consisting of an FPGA-based hardware driving an autonomous roving robot. The obtained results demonstrate the capability to perform a real-time navigation control.     

Deciphering the Genomic Landscape and Pharmacological Profile of Uncommon Entities of Adult Rhabdomyosarcomas

Adult rhabdomyosarcoma (RMS) represents an uncommon entity with an incidence of less than 3% of all soft tissue sarcomas (STS). Consequently, the natural history and the clinical management of this disease are infrequently reported. In order to fill this gap, we investigated the molecular biology of an adult RMS case series. The expression of epithelial mesenchymal transition-related gene and chemoresistance-related gene panels were evaluated. Moreover, taking advantage of our STS translational model combining patient-derived primary culture and 3D-scaffold, the pharmacological profile of an adult head and neck sclerosing RMS was assessed. Furthermore, NGS, microsatellite instability, and in silico analyses were carried out. RT-PCR identified the upregulation of CDH1, SLUG, MMP9, RAB22a, S100P, and LAPTM4b, representing promising biomarkers for this disease. Pharmacological profiling showed the highest sensitivity with anthracycline-based regimen in both 2D and 3D culture systems. NGS analysis detected RAB3IP-HMGA2 in frame gene rearrangement and FGFR4 mutation; microsatellite instability analysis did not detect any alteration. In silico analysis confirmed the mutation of FGFR4 as a promising marker for poor prognosis and a potential therapeutic target. We report for the first time the molecular and pharmacological characterization of rare entities of adult head and neck and posterior trunk RMS. These preliminary data could shed light on this poorly understood disease.     

iPSCs: A Preclinical Drug Research Tool for Neurological Disorders

The development and commercialization of new drugs is an articulated, lengthy, and very expensive process that proceeds through several steps, starting from target identification, screening new leading compounds for testing in preclinical studies, and subsequently in clinical trials to reach the final approval for therapeutic use. Preclinical studies are usually performed using both cell cultures and animal models, although they do not completely resume the complexity of human diseases, in particular neurodegenerative conditions. To this regard, stem cells represent a powerful tool in all steps of drug discovery. The recent advancement in induced Pluripotent Stem Cells (iPSCs) technology has opened the possibility to obtain patient-specific disease models for drug screening and development. Here, we report the use of iPSCs as a disease model for drug development in the contest of neurological disorders, including Alzheimer’s (AD) and Parkinson’s disease (PD), Amyotrophic lateral Sclerosis (ALS), and Fragile X syndrome (FRAX).