Fully digital intensity modulated LIDAR

AbstractIn several applications, such as collision avoidance, it is necessary to have a system able to rapidly detect the simultaneous presence of different obstacles. In general, these applications do not require high resolution performance, but it is necessary to assure high system reliability also within critical scenarios, as in the case of partially transparent atmosphere or environment in presence of multiple objects (implying multiple echoes having different delay times.) This paper describes the algorithm, the architecture and the implementation of a digital Light Detection and Ranging (LIDAR) system based on a chirped optical carrier. This technique provides some advantages compared to the pulsed approach, primarily the reduction of the peak power of the laser. In the proposed architecture all the algorithms for signal processing are implemented using digital hardware. In this way, some specific advantages are obtained: improved detection performance (larger dynamics, range and resolution), capability of detecting multiple obstacles having different echoes amplitude, reduction of the noise effects, reduction of the costs, size and weight of the resulting equipment. The improvement provided by this fully digital solution is potentially useful in different applications such as: collision avoidance systems, 3D mapping of environments and, in general, remote sensing systems which need wide distance and dynamics

Nutrition and IBD: Malnutrition and/or Sarcopenia? A Practical Guide

Malnutrition is a major complication of inflammatory bowel disease (IBD). This mini review is focusing on main determinants of malnutrition in IBD, the most important components of malnutrition, including lean mass loss and sarcopenia, as an emerging problem. Each one of these components needs to be well considered in a correct nutritional evaluation of an IBD patient in order to build a correct multidisciplinary approach. The review is then focusing on possible instrumental and clinical armamentarium for the nutritional evaluation

Characterization of Sarcopenia in an IBD Population Attending an Italian Gastroenterology Tertiary Center

(1) Background: There is growing interest in the assessment of muscular mass in inflammatory bowel disease (IBD) as sarcopenia is associated with important outcomes. The aim of the study was to evaluate the percentage of sarcopenia in IBD patients, characterizing methods for assessment and clinical symptoms associated to it. (2) Methods: Consecutive IBD patients accessing the Fondazione Policlinico Agostino Gemelli Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) were enrolled. Healthy patients, elderly or elderly sarcopenic patients, were enrolled as controls. Skeletal muscle mass was evaluated by Dual Energy X-ray Absorptiometry (DEXA) or Bio-Impedensometric Analysis (BIA). Asthenia degree was assessed by subjective visual analogue scales (VAS). Quality of life was measured by the EQ-5D questionnaire. (3) Results: Patients with IBD showed a significant reduction in skeletal muscle mass than healthy controls with lower DEXA and BIA parameters. Moreover, IBD patients presented a lower perception of muscle strength with a higher incidence of asthenia and reduction in quality of life when compared with healthy controls. A significant association between loss in skeletal muscle mass and high asthenia degree was found, configuring a condition of sarcopenia in about one third of patients with IBD. (4) Conclusions: Sarcopenia is common in IBD patients and it is associated with fatigue perception as well as a reduction in quality of life. Therefore, routine assessment of nutritional status and body composition should be a cornerstone in clinical practice, bringing gastroenterologists and nutritionists closer together for a compact, defined picture

Design, synthesis and optoelectronic properties of aminoacid derivatives of poly(Arylene ethynylene) platforms: Hybrid bio-synthetic systems for sensoring applications

By means of the modular construction of a large series of poly(arylene ethynylene)s (PAEs) employing Pd-promoted synthetic routes, molecular models of type A-CºC-B-CºC-A and B-CºC-A-CC-B, and polymers of type [-CC-A-]n and [-CC-A-CC-B-]n carrying a variety of aminoacidic side arms, have been prepared and fully characterized towards their application as sensing materials. The introduction of different aminoacidic groups as side substituents on the conjugated backbone may allow the tuning of the recognition ability of the receptor site towards given analytes. The luminescent sensing properties of these materials towards metal ions were investigated. The flexibility of the synthetic route allows tuning of binding activity, molecular recognition and opto-and electro-properties of the materials, as well as the responses upon exposure to metal ions. All compounds showed high selectivity towards Hg(II) ions, and a signal amplification in Hg(II) detection was observed for the polymeric compound in comparison with small molecule analogues. Further functionalization of aminoacid substituted PAEs with ferrocene moieties allows the electrochemical sensing by change in the oxidation potential of Fe(II)/Fe(III) redox couple, and its dependence with the interaction of aminoacidic side arms with given analytes. © 2015 Bentham Science Publisher

Design, Synthesis and Optoelectronic Properties of Aminoacid Derivatives of Poly(arylene ethynylene) Platforms: Hybrid Bio-Synthetic Systems for Sensoring Applications

By means of the modular construction of a large series of poly(arylene ethynylene)s (PAEs) employing Pd-promoted synthetic routes, molecular models of type A-C equivalent to C-B-C equivalent to C-A and B-C equivalent to C-A-C equivalent to C-B, and polymers of type [-C equivalent to C-A-] n and [-C equivalent to C-A-C equivalent to C-B-](n) carrying a variety of aminoacidic side arms, have been prepared and fully characterized towards their application as sensing materials. The introduction of different aminoacidic groups as side substituents on the conjugated backbone may allow the tuning of the recognition ability of the receptor site towards given analytes. The luminescent sensing properties of these materials towards metal ions were investigated. The flexibility of the synthetic route allows tuning of binding activity, molecular recognition and opto- and electro- properties of the materials, as well as the responses upon exposure to metal ions. All compounds showed high selectivity towards Hg(II) ions, and a signal amplification in Hg(II) detection was observed for the polymeric compound in comparison with small molecule analogues. Further functionalization of aminoacid substituted PAEs with ferrocene moieties allows the electrochemical sensing by change in the oxidation potential of Fe(II)/Fe(III) redox couple, and its dependence with the interaction of aminoacidic side arms with given analytes

Synthesis and photophysical properties of poly(arylene ethynylene) small-molecules and polymers derivatized with leucine substituents

Aminoacidic/peptidic functionalized poly(aryleneethynylenes) (PAEs) are bio-inspired smart hybrids of great potential as active components in sensing devices. These materials synergically combine the superb photophysical properties of highly ethynylated unsaturated backbones with the large possibility of aminoacid and peptide design towards specific target-analyte binding. Conformational changes and/or electron density variations occurring along the PAE conjugated path, as a consequence of analyte binding to the aminoacidic/peptidic receptor site, might dramatically change the optoelectronic properties of the material, thus signaling the presence of the analyte. In this paper, we have studied the photochemistry of two groups of L-leucine/polyarylene-etynylene small molecules and polymers with the aim of optimizing the photochemical performances of aminoacidic derivatized PAE structures, in view of their use for metal sensing. Taking into account that among the different chemical sensors, fluorescence-based ones present many advantages in terms of sensitivity, selectivity, no need of references, and multiple readout signals, we have searched for more insight into the evolution of the optical properties of oligomers and polymers as a function of the structure of the PAE aminoacidic assembling